Answer:
C. x = 4√7
Step-by-step explanation:
This is a right triangle
The hypotenuse is 3+8 (the radius is 3 and the exterior length is 8)
We can use the Pythagorean theorem
a^2 +b^2 = c^2
3^2 + x^2 = 11^2
9+x^2 = 121
Subtract 9 from each side
9-9 + x^2 = 121-9
x^2 = 112
Take the square root of each side
sqrt(x^2) = sqrt(112)
x = sqrt(16*7)
x = 4 sqrt(7)
