Answer
$x=-5,9$
Work Step by Step
Given: $x^2-4x=45$ or, $x^2-4x-45=0$
Need to use factorization to solve the quadratic equation.
This can be factorized as follows:
$x^2+5x-9x-45=0$
or, $(x+5)(x-9)=0$
Now $x+5=0$ and $x-9=0$
Roots are $x=-5,9$
