(3+5)2x2-13=x

Solution for (3+5)2x2-13=x equation:

(3+5)2x^2-13=x

We move all terms to the left:

(3+5)2x^2-13-(x)=0

We add all the numbers together, and all the variables

82x^2-x-13=0

We add all the numbers together, and all the variables

82x^2-1x-13=0

a = 82; b = -1; c = -13;
Δ = b2-4ac
Δ = -12-4·82·(-13)
Δ = 4265
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{-(-1)-\sqrt{4265}}{2*82}=\frac{1-\sqrt{4265}}{164}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+\sqrt{4265}}{2*82}=\frac{1+\sqrt{4265}}{164}
$