# 7.7.8. Rotation

In the figure below,

- A
- B
- C
- D

### Example

In the figure below,

### Solution

Step 1: Find the length of

Use Pythagoras' theorem, and solve for the length of

Step 2: Find the area of

The side lengths of a rotated image are the same as the corresponding side lengths of the original figure. Therefore,

Then, use the formula for the area of a triangle.

Step 3: Find the area of

Use

The base length

Step 4: Find the area of