5x(x+4)+10=30

Solution for 5x(x+4)+10=30 equation:

5x(x+4)+10=30

We move all terms to the left:

5x(x+4)+10-(30)=0

We add all the numbers together, and all the variables

5x(x+4)-20=0

We multiply parentheses

5x^2+20x-20=0

a = 5; b = 20; c = -20;
Δ = b2-4ac
Δ = 202-4·5·(-20)
Δ = 800
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:

$\sqrt{\Delta}=\sqrt{800}=\sqrt{400*2}=\sqrt{400}*\sqrt{2}=20\sqrt{2}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(20)-20\sqrt{2}}{2*5}=\frac{-20-20\sqrt{2}}{10}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(20)+20\sqrt{2}}{2*5}=\frac{-20+20\sqrt{2}}{10}
$