x^2-12x=-36

I got x=-6

1 answer

x ^ 2 - 12 x = - 36 Add 36 to both sides

x ^ 2 - 12 x + 36 = - 36 + 36

x ^ 2 - 12 x + 36 = 0

a = 1 , b = - 12 , c = 36

Quadratic Formula :

x1/2 = [ - b ± sqroot ( b ^ 2 - 4 a c ) ] / 2 a

x1/2 = [ - ( - 12 ) ± sqroot ( ( - 12 ) ^ 2 - 4 * 1 * 36 ) ] / 2 * 1

x1/2 = [ 12 ± sqroot ( 144 - 144 ) ] / 2

x1/2 = [ 12 ± sqroot ( 0 ) ] / 2

x1/2 = [ 12 ± 0 ] / 2

x1/2 = 12 / 2

x1/2 = 6

x = 6