Consider a quarter of a circle of radius 20. Let r be the radius of the circle inscribed in this quarter of a circle. Find r.
Choose one: A) 20*(sqr2 -1) B) 8*(sqr3 -1) C) 4*(sqr7 - 1) D) 12* (sqr7 -1) E) None of these
I got 20/(sqr2 +1) and just forgot to multiply by (sqr2 -1).   20*(sqr2 -1)nswer 20*(sqr2 -1)
<result>A</result>
Consider a quarter of a circle of radius 20. Let r be the radius of the circle inscribed in this quarter of a circle. Find r.