(3x+8)(x-11)=0

Solution for (3x+8)(x-11)=0 equation:

(3x+8)(x-11)=0

We multiply parentheses ..

(+3x^2-33x+8x-88)=0

We get rid of parentheses

3x^2-33x+8x-88=0

We add all the numbers together, and all the variables

3x^2-25x-88=0

a = 3; b = -25; c = -88;
Δ = b2-4ac
Δ = -252-4·3·(-88)
Δ = 1681
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1681}=41$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-25)-41}{2*3}=\frac{-16}{6}
=-2+2/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-25)+41}{2*3}=\frac{66}{6}
=11
$