I assume the inscribed circle is also tangent to the larger circle.
Draw a diagram. If the inscribed circle has radius r, then
r^2 + r^2 = (5-r)^2
r = 5(√2-1)
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A quarter-circle with radius 5 is drawn. A circle is drawn inside the sector, which is tangent to the sides of the sector. Find the radius of the inscribed circle.
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