2021 Fall AMC 10A Problems/Problem 15
Isosceles triangle has , and a circle with radius is tangent to line at and to line at . What is the area of the circle that passes through vertices , , and
Solution 1
Let the center of the first circle be By Pythagorean Theorem, Now, notice that since is degrees, so arc is degrees and is the diameter. Thus, the radius is so the area is
- kante314
Solution 2 (Similar Triangles)
Because circle is tangent to at and to at
Solution in Progress
~KingRavi
See Also
2021 Fall AMC 10A (Problems • Answer Key • Resources) | ||
Preceded by Problem 14 |
Followed by Problem 16 | |
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