G.CO.C.10 - Prove Theorems About Triangles

In the diagram, triangle ABC is isosceles with AB=AC.

In triangle ABC, D is the midpoint of AC and E is the midpoint of BC.

Analyze the diagram below to answer the question.

Use the information below to find the perimeter of the triangle.

In triangle ABC, you want to conclude AB=AC. Which statements are sufficient on their own? Select all that apply.

Vertices A and B of triangle ABC are shown. Point G is the intersection of the medians.

Identify whether each pair of points supports the claim or is a counterexample.

Sara is working on the following geometric proof:

Erik makes the following claim:

Sam claims: “All right triangles are similar because they each have a right angle; by HL (right-triangle congruence) they’re all the same shape.”