X(x+10)=8(x+1)

Solution for X(x+10)=8(x+1) equation:

X(X+10)=8(X+1)

We move all terms to the left:

X(X+10)-(8(X+1))=0

We multiply parentheses

X^2+10X-(8(X+1))=0


We calculate terms in parentheses: -(8(X+1)), so:

8(X+1)

We multiply parentheses

8X+8

Back to the equation:

-(8X+8)


We get rid of parentheses

X^2+10X-8X-8=0

We add all the numbers together, and all the variables

X^2+2X-8=0

a = 1; b = 2; c = -8;
Δ = b2-4ac
Δ = 22-4·1·(-8)
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(2)-6}{2*1}=\frac{-8}{2}
=-4
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+6}{2*1}=\frac{4}{2}
=2
$