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Printsmc
geometry senior
Problem
Let be a rhombus with and . Let be a point on , and let and be the feet of the perpendiculars from to and , respectively. Which of the following is closest to the minimum possible value of ? 
(A)
(B)
(C)
(D)
Solution
Let the intersection of and be . Since is a rhombus, we have and . Since , we have , so . Therefore, By Pythagorean Theorem, The minimum value of would give the minimum value of , so we take the derivative (or use vertex form) to find that the minimum occurs when which gives . Hence, the minimum value of is , which is closest to .
Final answer
C