(x+8)(2x+5)=63

Solution for (x+8)(2x+5)=63 equation:

(x+8)(2x+5)=63

We move all terms to the left:

(x+8)(2x+5)-(63)=0

We multiply parentheses ..

(+2x^2+5x+16x+40)-63=0

We get rid of parentheses

2x^2+5x+16x+40-63=0

We add all the numbers together, and all the variables

2x^2+21x-23=0

a = 2; b = 21; c = -23;
Δ = b2-4ac
Δ = 212-4·2·(-23)
Δ = 625
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{625}=25$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(21)-25}{2*2}=\frac{-46}{4}
=-11+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(21)+25}{2*2}=\frac{4}{4}
=1
$