Problem: The base of an isosceles triangle is 6 inches and one of the equal sides is 12 inches. The radius of the circle through the vertices of the triangle is:
Answer Choices:
A. 5715
B. 43
C. 35
D. 63
E. none of these
Solution:
Let x be the distance from the center of the circle to the base and let Then
hh2+9r2∴r=r+xbe the altitude of △ABC.=144∴h=135=32+x2=32+(h−r)2=32+h2−2hr+r2=2h9+h2=21359+135=270144135=5815
