X(x+5)+x+(x+5)=86

Solution for X(x+5)+x+(x+5)=86 equation:

X(X+5)+X+(X+5)=86

We move all terms to the left:

X(X+5)+X+(X+5)-(86)=0

We add all the numbers together, and all the variables

X+X(X+5)+(X+5)-86=0

We multiply parentheses

X^2+X+5X+(X+5)-86=0

We get rid of parentheses

X^2+X+5X+X+5-86=0

We add all the numbers together, and all the variables

X^2+7X-81=0

a = 1; b = 7; c = -81;
Δ = b2-4ac
Δ = 72-4·1·(-81)
Δ = 373
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{-(7)-\sqrt{373}}{2*1}=\frac{-7-\sqrt{373}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+\sqrt{373}}{2*1}=\frac{-7+\sqrt{373}}{2}
$