6d ago

3 Views

0 Downloads

285.55 KB

9 Pages

Transcription

GeorgiaStandards of ExcellenceMathematicsStandardsGSE Geometry

Georgia Department of EducationK-12 Mathematics IntroductionGeorgia Mathematics focuses on actively engaging the student in the development of mathematicalunderstanding by working independently and cooperatively to solve problems, estimating and computingefficiently, using appropriate tools, concrete models and a variety of representations, and conductinginvestigations and recording findings. There is a shift toward applying mathematical concepts and skills in thecontext of authentic problems and student understanding of concepts rather than merely following a sequence ofprocedures. In mathematics classrooms, students will learn to think critically in a mathematical way with anunderstanding that there are many different solution pathways and sometimes more than one right answer inapplied mathematics. Mathematics is the economy of information. The central idea of all mathematics is todiscover how knowing some things leads, via reasoning, to knowing more—without having to commit theinformation to memory as a separate fact. It is the reasoned, logical connections that make mathematicscoherent. The implementation of the Georgia Standards of Excellence in Mathematics places the expectedemphasis on sense-making, problem solving, reasoning, representation, modeling, representation, connections,and communication.GeometryGeometry is the second course in a sequence of three required high school courses designed to ensure careerand college readiness. The course represents a discrete study of geometry with correlated statistics applications.The standards in the three-course high school sequence specify the mathematics that all students should study inorder to be college and career ready. Additional mathematics content is provided in fourth credit courses andadvanced courses including pre-calculus, calculus, advanced statistics, discrete mathematics, and mathematicsof finance courses. High school course content standards are listed by conceptual categories including Numberand Quantity, Algebra, Functions, Geometry, and Statistics and Probability. Conceptual categories portray acoherent view of high school mathematics content; a student’s work with functions, for example, crosses anumber of traditional course boundaries, potentially up through and including calculus. Standards forMathematical Practice provide the foundation for instruction and assessment.Mathematics Standards for Mathematical PracticeMathematical Practices are listed with each grade’s mathematical content standards to reflect theneed to connect the mathematical practices to mathematical content in instruction.The Standards for Mathematical Practice describe varieties of expertise that mathematics educators at all levelsshould seek to develop in their students. These practices rest on important “processes and proficiencies” withlongstanding importance in mathematics education. The first of these are the NCTM process standards ofproblem solving, reasoning and proof, communication, representation, and connections. The second are thestrands of mathematical proficiency specified in the National Research Council’s report Adding It Up: adaptivereasoning, strategic competence, conceptual understanding (comprehension of mathematical concepts,operations and relations), procedural fluency (skill in carrying out procedures flexibly, accurately, efficientlyand appropriately), and productive disposition (habitual inclination to see mathematics as sensible, useful, andworthwhile, coupled with a belief in diligence and one’s own efficacy).Richard Woods, State School SuperintendentJuly 2016 Page 2 of 9All Rights Reserved

Georgia Department of Education1 Make sense of problems and persevere in solving them.High school students start to examine problems by explaining to themselves the meaning of a problem andlooking for entry points to its solution. They analyze givens, constraints, relationships, and goals. They makeconjectures about the form and meaning of the solution and plan a solution pathway rather than simply jumpinginto a solution attempt. They consider analogous problems, and try special cases and simpler forms of theoriginal problem in order to gain insight into its solution. They monitor and evaluate their progress and changecourse if necessary. Older students might, depending on the context of the problem, transform algebraicexpressions or change the viewing window on their graphing calculator to get the information they need. Byhigh school, students can explain correspondences between equations, verbal descriptions, tables, and graphs ordraw diagrams of important features and relationships, graph data, and search for regularity or trends. Theycheck their answers to problems using different methods and continually ask themselves, “Does this makesense?” They can understand the approaches of others to solving complex problems and identifycorrespondences between different approaches.2 Reason abstractly and quantitatively.High school students seek to make sense of quantities and their relationships in problem situations. Theyabstract a given situation and represent it symbolically, manipulate the representing symbols, and pause asneeded during the manipulation process in order to probe into the referents for the symbols involved. Studentsuse quantitative reasoning to create coherent representations of the problem at hand; consider the units involved;attend to the meaning of quantities, not just how to compute them; and know and flexibly use differentproperties of operations and objects.3 Construct viable arguments and critique the reasoning of others.High school students understand and use stated assumptions, definitions, and previously established results inconstructing arguments. They make conjectures and build a logical progression of statements to explore the truthof their conjectures. They are able to analyze situations by breaking them into cases, and can recognize and usecounterexamples. They justify their conclusions, communicate them to others, and respond to the arguments ofothers. They reason inductively about data, making plausible arguments that take into account the context fromwhich the data arose. High school students are also able to compare the effectiveness of two plausiblearguments, distinguish correct logic or reasoning from that which is flawed, and—if there is a flaw in anargument—explain what it is. High school students learn to determine domains to which an argument applies,listen or read the arguments of others, decide whether they make sense, and ask useful questions to clarify orimprove the arguments.4 Model with mathematics.High school students can apply the mathematics they know to solve problems arising in everyday life, society,and the workplace. By high school, a student might use geometry to solve a design problem or use a function todescribe how one quantity of interest depends on another. High school students making assumptions andapproximations to simplify a complicated situation, realizing that these may need revision later. They are able toidentify important quantities in a practical situation and map their relationships using such tools as diagrams,two-way tables, graphs, flowcharts and formulas. They can analyze those relationships mathematically to drawconclusions. They routinely interpret their mathematical results in the context of the situation and reflect onwhether the results make sense, possibly improving the model if it has not served its purpose.Richard Woods, State School SuperintendentJuly 2016 Page 3 of 9All Rights Reserved

Georgia Department of Education5 Use appropriate tools strategically.High school students consider the available tools when solving a mathematical problem. These tools mightinclude pencil and paper, concrete models, a ruler, a protractor, a calculator, a spreadsheet, a computer algebrasystem, a statistical package, or dynamic geometry software. High school students should be sufficientlyfamiliar with tools appropriate for their grade or course to make sound decisions about when each of these toolsmight be helpful, recognizing both the insight to be gained and their limitations. For example, high schoolstudents analyze graphs of functions and solutions generated using a graphing calculator. They detect possibleerrors by strategically using estimation and other mathematical knowledge. When making mathematical models,they know that technology can enable them to visualize the results of varying assumptions, exploreconsequences, and compare predictions with data. They are able to identify relevant external mathematicalresources, such as digital content located on a website, and use them to pose or solve problems. They are able touse technological tools to explore and deepen their understanding of concepts.6 Attend to precision. High school students try to communicate precisely to others by using clear definitions indiscussion with others and in their own reasoning. They state the meaning of the symbols they choose,specifying units of measure, and labeling axes to clarify the correspondence with quantities in a problem. Theycalculate accurately and efficiently, express numerical answers with a degree of precision appropriate for theproblem context. By the time they reach high school they have learned to examine claims and make explicit useof definitions.7 Look for and make use of structure. By high school, students look closely to discern a pattern or structure.In the expression x2 9x 14, older students can see the 14 as 2 7 and the 9 as 2 7. They recognize thesignificance of an existing line in a geometric figure and can use the strategy of drawing an auxiliary line forsolving problems. They also can step back for an overview and shift perspective. They can see complicatedthings, such as some algebraic expressions, as single objects or as being composed of several objects. Forexample, they can see 5 – 3(x – y)2 as 5 minus a positive number times a square and use that to realize that itsvalue cannot be more than 5 for any real numbers x and y. High school students use these patterns to createequivalent expressions, factor and solve equations, and compose functions, and transform figures.8 Look for and express regularity in repeated reasoning.High school students notice if calculations are repeated, and look both for general methods and for shortcuts.Noticing the regularity in the way terms cancel when expanding (x – 1)(x 1), (x – 1)(x2 x 1), and (x – 1)(x3 x2 x 1) might lead them to the general formula for the sum of a geometric series. As they work to solve aproblem, derive formulas or make generalizations, high school students maintain oversight of the process, whileattending to the details. They continually evaluate the reasonableness of their intermediate results.Connecting the Standards for Mathematical Practice to the Standards for Mathematical ContentThe Standards for Mathematical Practice describe ways in which developing student practitioners of thediscipline of mathematics should engage with the subject matter as they grow in mathematical maturity andexpertise throughout the elementary, middle and high school years. Designers of curricula, assessments, andprofessional development should all attend to the need to connect the mathematical practices to mathematicalcontent in mathematics instruction.The Standards for Mathematical Content are a balanced combination of procedure and understanding.Expectations that begin with the word “understand” are often especially good opportunities to connect theRichard Woods, State School SuperintendentJuly 2016 Page 4 of 9All Rights Reserved

Georgia Department of Educationpractices to the content. Students who do not have an understanding of a topic may rely on procedures tooheavily. Without a flexible base from which to work, they may be less likely to consider analogous problems,represent problems coherently, justify conclusions, apply the mathematics to practical situations, use technologymindfully to work with the mathematics, explain the mathematics accurately to other students, step back for anoverview, or deviate from a known procedure to find a shortcut. In short, a lack of understanding effectivelyprevents a student from engaging in the mathematical practices.In this respect, those content standards which set an expectation of understanding are potential “points ofintersection” between the Standards for Mathematical Content and the Standards for Mathematical Practice.These points of intersection are intended to be weighted toward central and generative concepts in the schoolmathematics curriculum that most merit the time, resources, innovative energies, and focus necessary toqualitatively improve the curriculum, instruction, assessment, professional development, and studentachievement in mathematics.Geometry Content StandardsCongruenceG.COExperiment with transformations in the planeMGSE9-12.G.CO.1 Know precise definitions of angle, circle, perpendicular line, parallel line, and linesegment, based on the undefined notions of point, line, distance along a line, and distance around a circular arc.MGSE9-12.G.CO.2 Represent transformations in the plane using, e.g., transparencies and geometry software;describe transformations as functions that take points in the plane as inputs and give other points as outputs.Compare transformations that preserve distance and angle to those that do not (e.g., translation versus horizontalstretch).MGSE9-12.G.CO.3 Given a rectangle, parallelogram, trapezoid, or regular polygon, describe the rotations andreflections that carry it onto itself.MGSE9-12.G.CO.4 Develop definitions of rotations, reflections, and translations in terms of angles, circles,perpendicular lines, parallel lines, and line segments.MGSE9-12.G.CO.5 Given a geometric figure and a rotation, reflection, or translation, draw the transformedfigure using, e.g., graph paper, tracing paper, or geometry software. Specify a sequence of transformations thatwill carry a given figure onto another.Understand congruence in terms of rigid motionsMGSE9-12.G.CO.6 Use geometric descriptions of rigid motions to transform figures and to predict the effect ofa given rigid motion on a given figure; given two figures, use the definition of congruence in terms of rigidmotions to decide if they are congruent.MGSE9-12.G.CO.7 Use the definition of congruence in terms of rigid motions to show that two triangles arecongruent if and only if corresponding pairs of sides and corresponding pairs of angles are congruent.MGSE9-12.G.CO.8 Explain how the criteria for triangle congruence (ASA, SAS, and SSS) follow from thedefinition of congruence in terms of rigid motions. (Extend to include HL and AAS.)Richard Woods, State School SuperintendentJuly 2016 Page 5 of 9All Rights Reserved

Georgia Department of EducationProve geometric theoremsMGSE9-12.G.CO.9 Prove theorems about lines and angles. Theorems include: vertical angles are congruent;when a transversal crosses parallel lines, alternate interior angles are congruent and corresponding angles arecongruent; points on a perpendicular bisector of a line segment are exactly those equidistant from the segment’sendpoints.MGSE9-12.G.CO.10 Prove theorems about triangles. Theorems include: measures of interior angles of atriangle sum to 180 degrees; base angles of isosceles triangles are congruent; the segment joining midpoints oftwo sides of a triangle is parallel to the third side and half the length; the medians of a triangle meet at a point.MGSE9-12.G.CO.11 Prove theorems about parallelograms. Theorems include: opposite sides are congruent,opposite angles are congruent, the diagonals of a parallelogram bisect each other, and conversely, rectangles areparallelograms with congruent diagonals.Make geometric constructionsMGSE9-12.G.CO.12 Make formal geometric constructions with a variety of tools and methods (compass andstraightedge, string, reflective devices, paper folding, dynamic geometric software, etc.). Copying a segment;copying an angle; bisecting a segment; bisecting an angle; constructing perpendicular lines, including theperpendicular bisector of a line segment; and constructing a line parallel to a given line through a point not onthe line.MGSE9-12.G.CO.13 Construct an equilateral triangle, a square, and a regular hexagon, each inscribed in acircle.Similarity, Right Triangles, and TrigonometryG.SRTUnderstand similarity in terms of similarity transformationsMGSE9-12.G.SRT.1 Verify experimentally the properties of dilations given by a center and a scale factor.a. The dilation of a line not passing through the center of the dilation results in a parallel line and leaves aline passing through the center unchanged.b. The dilation of a line segment is longer or shorter according to the ratio given by the scale factor.MGSE9-12.G.SRT.2 Given two figures, use the definition of similarity in terms of similarity transformations todecide if they are similar; explain, using similarity transformations, the meaning of similarity for triangles as theequality of all corresponding pairs of angles and the proportionality of all corresponding pairs of sides.MGSE9-12.G.SRT.3 Use the properties of similarity transformations to establish the AA criterion for twotriangles to be similar.Prove theorems involving similarityMGSE9-12.G.SRT.4 Prove theorems about triangles. Theorems include: a line parallel to one side of a triangledivides the other two proportionally, (and its converse); the Pythagorean Theorem using triangle similarity.Richard Woods, State School SuperintendentJuly 2016 Page 6 of 9All Rights Reserved

Georgia Department of EducationMGSE9-12.G.SRT.5 Use congruence and similarity criteria for triangles to solve problems and to proverelationships in geometric figures.Define trigonometric ratios and solve problems involving right trianglesMGSE9-12.G.SRT.6 Understand that by similarity, side ratios in right triangles are properties of the angles inthe triangle, leading to definitions of trigonometric ratios for acute angles.MGSE9-12.G.SRT.7 Explain and use the relationship between the sine and cosine of complementary angles.MGSE9-12.G.SRT.8 Use trigonometric ratios and the Pythagorean Theorem to solve right triangles in appliedproblems.CirclesG.CUnderstand and apply theorems about circlesMGSE9-12.G.C.1 Understand that all circles are similar.MGSE9-12.G.C.2 Identify and describe relationships among inscribed angles, radii, chords, tangents, andsecants. Include the relationship between central, inscribed, and circumscribed angles; inscribed angles on adiameter are right angles; the radius of a circle is perpendicular to the tangent where the radius intersects thecircle.MGSE9-12.G.C.3 Construct the inscribed and circumscribed circles of a triangle, and prove properties ofangles for a quadrilateral inscribed in a circle.MGSE9-12.G.C.4 Construct a tangent line from a point outside a given circle to the circle.Find arc lengths and areas of sectors of circlesMGSE9-12.G.C.5 Derive using similarity the fact that the length of the arc intercepted by an angle isproportional to the radius, and define the radian measure of the angle as the constant of proportionality; derivethe formula for the area of a sector.Expressing Geometric Properties with EquationsG.GPETranslate between the geometric description and the equation for a conic sectionMGSE9-12.G.GPE.1 Derive the equation of a circle of given center and radius using the Pythagorean Theorem;complete the square to find the center and radius of a circle given by an equation.Use coordinates to prove simple geometric theorems algebraicallyMGSE9-12.G.GPE.4 Use coordinates to prove simple geometric theorems algebraically. For example, proveor disprove that a figure defined by four given points in the coordinate plane is a rectangle; prove or disprovethat the point (1, 3) lies on the circle centered at the origin and containing the point (0,2).(Focus on quadrilaterals, right triangles, and circles.)Richard Woods, State School SuperintendentJuly 2016 Page 7 of 9All Rights Reserved

Georgia Department of EducationMGSE9-12.G.GPE.5 Prove the slope criteria for parallel and perpendicular lines and use them to solvegeometric problems (e.g., find the equation of a line parallel or perpendicular to a given line that passes througha given point).MGSE9-12.G.GPE.6 Find the point on a directed line segment between two given points that partitions thesegment in a given ratio.MGSE9-12.G.GPE.7 Use coordinates to compute perimeters of polygons and areas of triangles and rectangles,e.g., using the distance formula.Geometric Measurement and DimensionG.GMDExplain volume formulas and use them to solve problemsMGSE9-12.G.GMD.1 Give informal arguments for geometric formulas.a. Give informal arguments for the formulas of the circumference of a circle and area of a circle usingdissection arguments and informal limit arguments.b. Give informal arguments for the formula of the volume of a cylinder, pyramid, and cone usingCavalieri’s principle.MGSE9-12.G.GMD.2 Give an informal argument using Cavalieri’s principle for the formulas for the volume ofa sphere and other solid figures.MGSE9-12.G.GMD.3 Use volume formulas for cylinders, pyramids, cones, and spheres to solve problems.Visualize relationships between two-dimensional and three-dimensional objectsMGSE9-12.G.GMD.4 Identify the shapes of two-dimensional cross-sections of three-dimensional objects, andidentify three-dimensional objects generated by rotations of two-dimensional objects.Modeling with GeometryG.MGApply geometric concepts in modeling situationsMGSE9-12.G.MG.1 Use geometric shapes, their measures, and their properties to describe objects(e.g., modeling a tree trunk or a human torso as a cylinder).MGSE9-12.G.MG.2 Apply concepts of density based on area and volume in modeling situations(e.g., persons per square mile, BTUs per cubic foot).MGSE9-12.G.MG.3 Apply geometric methods to solve design problems (e.g., designing an object or structureto satisfy physical constraints or minimize cost; working with typographic grid systems based on ratios).Conditional Probability and the Rules of ProbabilityS.CPUnderstand independence and conditional probability and use them to interpret dataMGSE9-12.S.CP.1 Describe categories of events as subsets of a sample space using unions, intersections, orcomplements of other events (or, and, not).Richard Woods, State School SuperintendentJuly 2016 Page 8 of 9All Rights Reserved

Georgia Department of EducationMGSE9-12.S.CP.2 Understand that if two events A and B are independent, the probability of A and Boccurring together is the product of their probabilities, and that if the probability of two events A and Boccurring together is the product of their probabilities, the two events are independent.MGSE9-12.S.CP.3 Understand the conditional probability of A given B as P (A and B)/P(B). Interpretindependence of A and B in terms of conditional probability; that is, the conditional probability of A given B isthe same as the probability of A, and the conditional probability of B given A is the same as the probability of B.MGSE9-12.S.CP.4 Construct and interpret two-way frequency tables of data when two categories areassociated with each object being classified. Use the two-way table as a sample space to decide if events areindependent and to approximate conditional probabilities. For example, use collected data from a randomsample of students in your school on their favorite subject among math, science, and English. Estimate theprobability that a randomly selected student from your school will favor science given that the student is in tenthgrade. Do the same for other subjects and compare the results.MGSE9-12.S.CP.5 Recognize and explain the concepts of conditional probability and independence ineveryday language and everyday situations. For example, compare the chance of having lung cancer if you area smoker with the chance of being a smoker if you have lung cancer.Use the rules of probability to compute probabilities of compound events in a uniform probability modelMGSE9-12.S.CP.6 Find the conditional probability of A given B as the fraction of B’s outcomes that alsobelong to A, and interpret the answer in context.MGSE9-12.S.CP.7 Apply the Addition Rule, P(A or B) P(A) P(B) – P(A and B), and interpret the answersin context.Richard Woods, State School SuperintendentJuly 2016 Page 9 of 9All Rights Reserved

Geometry Geometry is the second course in a sequence of three required high school courses designed to ensure career and college readiness. The course represents a discrete study of geometry with correlated statistics applications. . The Standards for Mathematical Practice describe variet