Download Sample 5.3.B.2 Complete

G.CO.9-11
2011
Domain Congruence
Cluster Prove geometric theorems
Standards
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 are congruent; points on a perpendicular bisector of a line
segment are exactly those equidistant from the segment’s endpoints.
10. Prove theorems about triangles. Theorems include: measures of interior angles of a triangle sum to 180°; base angles of
isosceles triangles are congruent; the segment joining midpoints of two sides of a triangle is parallel to the third side and half the
length; the medians of a triangle meet at a point.
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 are parallelograms with congruent diagonals.
Essential Questions
Enduring Understandings
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What is a geometric
proof?
Why do we have to
prove statements that
have already been
proven by
mathematicians of the
past?
Content Statements
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Students will be able to
apply definitions,
theorems, postulates
and properties about
vertical angles, parallel
lines, perpendicular
lines, bisectors,
triangles, and
parallelograms to
Student will understand that
practicing geometric proofs
teaches the logic of
deductive reasoning.
Activities, Investigation, and Student Experiences
1. PowerPoint lessons, Interactive Examples, Worksheets,
Activities
2. SMARTboard lessons and examples
3. Multiple Sample Lessons and Examples
G.CO.9-11
2011
develop and justify a
geometric proof.
Assessments
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Student Participation
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Questioning
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Quizzes (Teacher Given and Self Quizzes)
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Benchmark/Test (Click here for Resources
Folder.)
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Homework
Equipment Needed:
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SMARTboard
Projector
Paper and pencil
Calculator (Graphing and Scientific)
Compass
Protractor
Ruler
Straightedge
Graph Paper
Isometric Dot Paper
Hands-on and virtual two- and three-dimensional
manipulatives (i.e. prisms)
Geo-boards
Teacher Resources:
1. Math Warehouse Website:
http://www.mathwarehouse.com/geometry/angle/interactivetransveral-angles.php
2. Click here for Resources Folder.
3. Click here for Resources Folder.
G.CO.9-11
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Geometer’s Sketchpad
2011