solve for x

x^2+45=6x. is this like completing the square

yes, you can complete the square for solving quadratics

first get the x^2 term and the x term to one side and the constant to the other.

x^2+45=6x
x^2 - 6x = -45
x^2 - 6x + 9 = -45 + 9
(x-3)^2 = -36
x-3 = ±√-36
x = 3 ± 6i , hope you know about complex numbers.