There are three points O, P, Q, O is the center of the circle, P and Q are two points on the circle, and ∠POQ is 45 °, then it seems that the area of a triangle is 12, Find the area of a circle ?
Hi there,
hope my explanation could help you.
As O is the center of the circle and P, Q are on the circle => OP = OQ = r (the radius of the circle)
The area of the triangle can be calculated by: S = 1/2 sin($$\angle$$ POQ) OP. OQ = 1/2 . $$\frac{\sqrt{2}}{2}$$ . OP . OQ
We have S = 12 => the value of OP.OQ
OP.OQ = r. r = $$r^2$$
The area of the circle: S' = $$\pi.r^2$$
You can get your answer now.
