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Standards/Math/District of Columbia/HSG.CO.C

HSG.CO.C

HSG.CO Congruence
HSG.CO.A
HSG.CO.B
HSG.CO.C
HSG.CO.C.10HSG.CO.C.11HSG.CO.C.9
HSG.CO.D

Prove geometric theorems

HSG.CO.C.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.HSG.CO.C.11Prove 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.HSG.CO.C.9Prove 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.
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