X^2+13x=72

Solution for X^2+13x=72 equation:

X^2+13X=72

We move all terms to the left:

X^2+13X-(72)=0

a = 1; b = 13; c = -72;
Δ = b2-4ac
Δ = 132-4·1·(-72)
Δ = 457
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(13)-\sqrt{457}}{2*1}=\frac{-13-\sqrt{457}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(13)+\sqrt{457}}{2*1}=\frac{-13+\sqrt{457}}{2}
$