Find an equation of the circle that has center (5,-2) and passes through (-5,-1).

Answer 1

Natasha,

The formula for a circle is as follows given the center is at (h,k) with a radius r.

 (x – h)² + (y – k)² = r²

 (x – 5)² + (y – (-2))² = r²

 (x – 5)² + (y + 2)² = r²

To find the radius we can use  Pythagorean theorem: r² = (x2−x1)2+(y2−y1)2

r² = (x2−x1)2+(y2−y1)2

r² = ((-5) - 5)2+((-1) - (-2))2

r² = (-25)2+(1)2 = 626



Answer:  (x – 5)² + (y + 2)² = 626

Answer 2

The equation would be (x-5)² + (y+2)² = 101