# 8.10.2. Converse of Pythagoras Theorem

If

- A
- B
- C
- D

### Example

If

### Solution

Step 1: Find the area of

Step 2: Find the length of

Use Pythagoras' theorem, which states that the square of the length of a right triangle's hypotenuse is equal to the sum of the squares of the lengths of the other two sides.

Substitute the known lengths in

Step 3: Find the area of

The converse of Pythagoras' theorem states that if the square of
the length of a side is equal to the sum of the squares of the
other two sides, then the angle opposite to this side is a right
angle.

Step 4: Find the area of figure

Subtract the area of