2x2-20=120+x

Solution for 2x2-20=120+x equation:

2x^2-20=120+x

We move all terms to the left:

2x^2-20-(120+x)=0

We add all the numbers together, and all the variables

2x^2-(x+120)-20=0

We get rid of parentheses

2x^2-x-120-20=0

We add all the numbers together, and all the variables

2x^2-1x-140=0

a = 2; b = -1; c = -140;
Δ = b2-4ac
Δ = -12-4·2·(-140)
Δ = 1121
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{-(-1)-\sqrt{1121}}{2*2}=\frac{1-\sqrt{1121}}{4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+\sqrt{1121}}{2*2}=\frac{1+\sqrt{1121}}{4}
$