In the figure to the right if AC 20 and BC 17 what is the

In the figure to the right, if AC = 20 and BC = 17, what is the radius? The radius is approximately.

Solution

Clearly ABC is right angled triangle.

So by Pythagoras theorem we will have

AB² + BC² = AC²

AB^{2 +} 17² = 20²

   AB^2. = 20² - 17²

^.   AB² = 400 -289

AB² = 111

AB. = 10.5

Therefore radius =AB = 10.5 =11 (nearest tenth)

^.