Which of the following points lies on the circle whose center is at the origin and whose radius is 10?

Unfortunately, you haven't shared "the following points."

The equation of a circle centered at the origin and whose radius is 10 is

x^2 + y^2 = 10^2.

if a = 1,   and b = 2, then the answer is 47.99999999. if you round that to the nearest whole number, the answer is 48.

step-by-step explanation:

no, her answer is not correct.   we square the lengths of all sides and then determine whether the pythagorean theorem holds here:

9² + 15² = 306.   this is not equal to the square of the longest side ( that square being 395.   answer c is correct.