The steps for determining the center and radius of a circle using the completing the square method are shown below: step 1 [original equation]: x2 − 10x + y2 + 12y = 20 step 2 [group like terms]: (x2 − 10x) + (y2 + 12y) = 20 step 3 [complete the quadratics]: (x2 − 10x + 25) + (y2 + 12y + 36) = 20 + (25 + 36) step 4 [simplify the equation]: (x2 − 10x + 25) + (y2 + 12y + 36) = 64 step 5 [factor each quadratic]: (x − 5)2 + (y + 6)2 = 82 step 6 [identify the center and radius]: center = (5, −6) radius = 8 what is the first incorrect step, and how can it be fixed? a. step 3, replace 25 with 5 and replace 36 with 6 b. step 4, replace 64 with 81 c. step 5, replace − 5 with + 5 and replace + 6 with − 6 d. all steps are correct.