What is the standard form of the equation of a circle with its center at (2, -3) and passing through the point (-2, 0)?

A.(x − 2)2 + (y + 3)2 = 5

B.(x + 2)2 + (y − 3)2 = 25

C.(x − 2)2 + (y + 3)2 = 25

D.(x − 2)2 − (y + 3)2 = 5

Question

What is the standard form of the equation of a circle with its center at (2, -3) and passing through the point (-2, 0)?

A.(x − 2)2 + (y + 3)2 = 5

B.(x + 2)2 + (y − 3)2 = 25

C.(x − 2)2 + (y + 3)2 = 25 

D.(x − 2)2 − (y + 3)2 = 5

ddcamp · Answer

If the center is at (h,k), and the radius is r, the formula is
$$(x-h)^2 +(y-k)^2 = r^2$$

You already have the center point, but you need to find the radius. How do you think we should do that?