(X+15)x=33

Solution for (X+15)x=33 equation:

(X+15)X=33

We move all terms to the left:

(X+15)X-(33)=0

We multiply parentheses

X^2+15X-33=0

a = 1; b = 15; c = -33;
Δ = b2-4ac
Δ = 152-4·1·(-33)
Δ = 357
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{-(15)-\sqrt{357}}{2*1}=\frac{-15-\sqrt{357}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+\sqrt{357}}{2*1}=\frac{-15+\sqrt{357}}{2}
$