Question

Find the equation of a circle whose center is at (2, 3) and radius is 6.

a. (x + 2)² + ( y + 3)² = 6
b. (x + 2)² + ( y + 3)² = 36
c. (x – 2)² + ( y – 3)² = 36
d. (x – 2)² + ( y – 3)² = 6

Answer 1

Answer: C

Explanation: Using the formula :

(x - h)^2 + (y - k)^2 = r^2

The given points (2,3) is always opposite of its original sign.

(2,3) —> (-2,-3)

(x - 2)^2 + (y - 3)^2 = 36

Its equal 36 because 6 squared (6•6) is 36.
You can always use desmos to check the answer.