ABCD is a trapezoid with AB<CD and AB parallel to CD. Γ is a circle inscribed in ABCD, such that Γ is tangent to all four sides. If AD=BC=25 and the area of ABCD is 600, what is the radius of Γ?
The area of the triangle AOD is 1/4 of [ABCD].
To find a radius of a circle we ought to multiply [AOD] by 2 and then divide the product by 25.
r = 300 / 25