(8x-5)*(x+11)=0

Solution for (8x-5)*(x+11)=0 equation:

(8x-5)(x+11)=0

We multiply parentheses ..

(+8x^2+88x-5x-55)=0

We get rid of parentheses

8x^2+88x-5x-55=0

We add all the numbers together, and all the variables

8x^2+83x-55=0

a = 8; b = 83; c = -55;
Δ = b2-4ac
Δ = 832-4·8·(-55)
Δ = 8649
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{8649}=93$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(83)-93}{2*8}=\frac{-176}{16}
=-11
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(83)+93}{2*8}=\frac{10}{16}
=5/8
$