Question

what is an equation of a circle with its center at(-3,5) and a radius of 4

Answer 1

ttp://www.mathwarehouse.com/geometry/circle/images/equation-of-circle/example-2-equation-of-circle.png

Answer 2

\[(x-h)^2+(y-k)^2 = r^2\]is the general formula for a circle with radius \(r\) and center at \((h,k)\)
You just have to plug in the numbers (and be careful about subtracting negative numbers!).