8x^2-20x-6x-45=0

Solution for 8x^2-20x-6x-45=0 equation:

8x^2-20x-6x-45=0

We add all the numbers together, and all the variables

8x^2-26x-45=0

a = 8; b = -26; c = -45;
Δ = b2-4ac
Δ = -262-4·8·(-45)
Δ = 2116
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2116}=46$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-26)-46}{2*8}=\frac{-20}{16}
=-1+1/4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-26)+46}{2*8}=\frac{72}{16}
=4+1/2
$