Answer:
28.26 square inches
Step-by-step explanation:
Formula for area of a circle:

Radius is 3.

Use 3.14 for pi:

The area should be 28.26 square inches.
D. since if you plug in the Pythagorean therom it comes out true and the Pythagorean therom only works on right triangles. also isosceles have 2 side lengths the same.
The diagonals are congruent.
hope this helped.