700=x^2+60x

Solution for 700=x^2+60x equation:

700=x^2+60x

We move all terms to the left:

700-(x^2+60x)=0

We get rid of parentheses

-x^2-60x+700=0

We add all the numbers together, and all the variables

-1x^2-60x+700=0

a = -1; b = -60; c = +700;
Δ = b2-4ac
Δ = -602-4·(-1)·700
Δ = 6400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{6400}=80$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-60)-80}{2*-1}=\frac{-20}{-2}
=+10
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-60)+80}{2*-1}=\frac{140}{-2}
=-70
$