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Printsmc
geometry senior
Problem
A circle with center is tangent to the coordinate axes and to the hypotenuse of the -- triangle as shown, where . To the nearest hundredth, what is the radius of the circle? 
(A)
(B)
(C)
(D)
Solution
Draw radii and to the axes, and label the point of tangency to triangle point . Let the radius of the circle be . Square has side length . Because and are tangents from a common point , . Similarly, , and we can write: Equating the radii lengths, we have This means by the 30-60-90 triangle. Therefore, , and we get The radius of the circle is , which is Using decimal approximations, , and the answer is .
Final answer
D