x^2-4x^2-45x=0

Solution for x^2-4x^2-45x=0 equation:

x^2-4x^2-45x=0

We add all the numbers together, and all the variables

-3x^2-45x=0

a = -3; b = -45; c = 0;
Δ = b2-4ac
Δ = -452-4·(-3)·0
Δ = 2025
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2025}=45$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-45)-45}{2*-3}=\frac{0}{-6}
=0
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-45)+45}{2*-3}=\frac{90}{-6}
=-15
$