X2-9x+18=2x+8

Solution for X2-9x+18=2x+8 equation:

X2-9X+18=2X+8

We move all terms to the left:

X2-9X+18-(2X+8)=0

We add all the numbers together, and all the variables

X^2-9X-(2X+8)+18=0

We get rid of parentheses

X^2-9X-2X-8+18=0

We add all the numbers together, and all the variables

X^2-11X+10=0

a = 1; b = -11; c = +10;
Δ = b2-4ac
Δ = -112-4·1·10
Δ = 81
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{81}=9$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-11)-9}{2*1}=\frac{2}{2}
=1
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-11)+9}{2*1}=\frac{20}{2}
=10
$