Geometry-Angles-Triangles- I need help

The closest answer to this is C=12

Step-by-step explanation:

With isosceles triangles we know 2 sides are equal and the base angles are equal. We have to find the value of x which is the third side of the triangle. We can see half of x is the third side of another triangle formed. we can use the Pythagorean theorem find the leg of half of one of the triangles.

We have to take the square root of this to get 1/2 of x..

B= about  6.35591651

If we muiltply this by 2 we get around 12.711833

The closest answer to this is C=12

circle area = pi * radius^2

if diameter = 10 then radius = 5

circle area = pi * 5^2

circle area = pi * 25

circle area = 78.5398163397 square units

step-by-step explanation: