119=5x(x+4)

Solution for 119=5x(x+4) equation:

119=5x(x+4)

We move all terms to the left:

119-(5x(x+4))=0


We calculate terms in parentheses: -(5x(x+4)), so:

5x(x+4)

We multiply parentheses

5x^2+20x

Back to the equation:

-(5x^2+20x)


We get rid of parentheses

-5x^2-20x+119=0

a = -5; b = -20; c = +119;
Δ = b2-4ac
Δ = -202-4·(-5)·119
Δ = 2780
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{2780}=\sqrt{4*695}=\sqrt{4}*\sqrt{695}=2\sqrt{695}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-20)-2\sqrt{695}}{2*-5}=\frac{20-2\sqrt{695}}{-10}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-20)+2\sqrt{695}}{2*-5}=\frac{20+2\sqrt{695}}{-10}
$