A circle equation is : ( x - p )² + ( y - q )² = r², where p and q are coordinates of the center. The position of the source is : ( - 6, - 4 ) and the range : r² = 36 ⇒ r = 6
Just for future reference always put ^ for exponents. The answer is y-6 though. (y-4)(y-6) create that trinomial. You can prove that by using the FOIL algorithm
