13x2-18=-13x-18

Solution for 13x2-18=-13x-18 equation:

13x^2-18=-13x-18

We move all terms to the left:

13x^2-18-(-13x-18)=0

We get rid of parentheses

13x^2+13x+18-18=0

We add all the numbers together, and all the variables

13x^2+13x=0

a = 13; b = 13; c = 0;
Δ = b2-4ac
Δ = 132-4·13·0
Δ = 169
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{169}=13$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(13)-13}{2*13}=\frac{-26}{26}
=-1
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(13)+13}{2*13}=\frac{0}{26}
=0
$