Practice Geometric Proofs in Math
Use these practice problems to test your method after reviewing the concept explanation and worked examples.
Quick Recap
Geometric proofs establish that a geometric claim is true by chaining justified statements from definitions, theorems, and givens.
It is a legal argument where each line needs a valid reason.
Example 1
mediumProve that the base angles of an isosceles triangle are equal.
Example 2
hardProve by contradiction: if two lines are cut by a transversal so that alternate interior angles are equal, the lines are parallel.
Example 3
easyProve that vertical angles are equal. Given: Lines AB and CD intersect at O; prove \angle AOC = \angle BOD.
Example 4
mediumGiven that \triangle ABC \cong \triangle DEF, prove that the perimeters are equal.