5*(29.6-x)x=13

Solution for 5*(29.6-x)x=13 equation:

5*(29.6-x)x=13

We move all terms to the left:

5*(29.6-x)x-(13)=0

We add all the numbers together, and all the variables

5*(-1x+29.6)x-13=0

We multiply parentheses

-5x^2+148x-13=0

a = -5; b = 148; c = -13;
Δ = b2-4ac
Δ = 1482-4·(-5)·(-13)
Δ = 21644
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:

$\sqrt{\Delta}=\sqrt{21644}=\sqrt{4*5411}=\sqrt{4}*\sqrt{5411}=2\sqrt{5411}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(148)-2\sqrt{5411}}{2*-5}=\frac{-148-2\sqrt{5411}}{-10}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(148)+2\sqrt{5411}}{2*-5}=\frac{-148+2\sqrt{5411}}{-10}
$