x2+13x-12=7x-7

Solution for x2+13x-12=7x-7 equation:

x2+13x-12=7x-7

We move all terms to the left:

x2+13x-12-(7x-7)=0

We add all the numbers together, and all the variables

x^2+13x-(7x-7)-12=0

We get rid of parentheses

x^2+13x-7x+7-12=0

We add all the numbers together, and all the variables

x^2+6x-5=0

a = 1; b = 6; c = -5;
Δ = b2-4ac
Δ = 62-4·1·(-5)
Δ = 56
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{56}=\sqrt{4*14}=\sqrt{4}*\sqrt{14}=2\sqrt{14}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(6)-2\sqrt{14}}{2*1}=\frac{-6-2\sqrt{14}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(6)+2\sqrt{14}}{2*1}=\frac{-6+2\sqrt{14}}{2}
$