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

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

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

We multiply parentheses ..

(+40x^2+88x+55x+121)=0

We get rid of parentheses

40x^2+88x+55x+121=0

We add all the numbers together, and all the variables

40x^2+143x+121=0

a = 40; b = 143; c = +121;
Δ = b2-4ac
Δ = 1432-4·40·121
Δ = 1089
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1089}=33$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(143)-33}{2*40}=\frac{-176}{80}
=-2+1/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(143)+33}{2*40}=\frac{-110}{80}
=-1+3/8
$