Problem:
What is the radius of a circle inscribed in a rhombus with diagonals of length and
Answer Choices:
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Solution:
Let be the intersection of the diagonals of a rhombus satisfying the conditions of the problem. Because these diagonals are perpendicular and bisect each other, is a right triangle with sides , and and area . Therefore the altitude drawn to side is , which is the radius of the inscribed circle centered at .
