X^2-21x=-110

Solution for X^2-21x=-110 equation:

X^2-21X=-110

We move all terms to the left:

X^2-21X-(-110)=0

We add all the numbers together, and all the variables

X^2-21X+110=0

a = 1; b = -21; c = +110;
Δ = b2-4ac
Δ = -212-4·1·110
Δ = 1
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1}=1$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-21)-1}{2*1}=\frac{20}{2}
=10
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-21)+1}{2*1}=\frac{22}{2}
=11
$