Question

Find the center of the circle whose equation is (x+15)2+(y-20)2=100

Answer 1

Answer: (- 15, 20)

Explanation:

In the format (x – h)² + (y – k) = r², the center of the circle is at point (h, k).

-> The negatives in the first equation, bolded and underlined, means we change the sign of positive to negative or negative to positive.

(x - h)² + (y - k) = r²

(x + 15)² + (y - 20)² = 100

(x - 15)² + (y + 20)² = 100

(x - 15)² + (y + 20)² = 100

(- 15, 20)

We can also see this with graphing. See attached.

The center of the circle will be at point (- 15, 20).