Hello,

I need help with this question:

"There is a triangle OAB. The length of AO is 10m and AOB has an angle of 0.8^{c}. This triangle also has an arc between points A and B."

Find the area of the triangle OAB

Find the area of the sector OAB

I have drawn the triangle to its correct description, see the attached image.

I have tried using the formula for the area of the sector 0.5r^{2}θ, but I got the answer to be 2193. This might be right, just seemed too big. But I do not know the formula for the area of the triangle! (I suppose this triangle is different to the formula 0.5xbxh)

Could you please help me work out how to find the area of this triangle?

Thanks in advance

Dan