### Home > INT2 > Chapter 10 > Lesson 10.2.3 > Problem 10-80

10-80.

Use the diagram of

If

, what is? Recall that the measure of each inscribed angle is half the arc it intercepts.

What is the sum of interior angles for triangles?

If

and, what is the area of ? Knowing that

is, use the Pythagorean Theorem to solve for the .Then from there, substitute the information you found in the equation for the area of a circle.

units ^{^2}If the radius of

is and if , what is ?Recall your trigonometric ratios.