154=15x+x^2

Solution for 154=15x+x^2 equation:

154=15x+x^2

We move all terms to the left:

154-(15x+x^2)=0

We get rid of parentheses

-x^2-15x+154=0

We add all the numbers together, and all the variables

-1x^2-15x+154=0

a = -1; b = -15; c = +154;
Δ = b2-4ac
Δ = -152-4·(-1)·154
Δ = 841
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{841}=29$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-15)-29}{2*-1}=\frac{-14}{-2}
=+7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-15)+29}{2*-1}=\frac{44}{-2}
=-22
$