Two squares share a vertex. Prove that the red triangle is congruent to the blue one.

Scroll down for a solution to this problem.

## Solution

This solution uses the inscribed angle theorem to show the top angles of the triangles are both 45°. Also it uses SAS to prove their congruence.

Please find here a nice animation by Amaresh G S showing all possibilities.

## Visual solution

## Poem

If we share our place

We have the same face

The triangles so sweet and small

Have to be patient first of all

Sometimes they try to say

Wanting to go out for freedom anyway

They share their colours too

1 twin is red the second blue

And listen so politely

Hello to you with glee