3x2+4=x+8

Solution for 3x2+4=x+8 equation:

3X^2+4=X+8

We move all terms to the left:

3X^2+4-(X+8)=0

We get rid of parentheses

3X^2-X-8+4=0

We add all the numbers together, and all the variables

3X^2-1X-4=0

a = 3; b = -1; c = -4;
Δ = b2-4ac
Δ = -12-4·3·(-4)
Δ = 49
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{49}=7$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1)-7}{2*3}=\frac{-6}{6}
=-1
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+7}{2*3}=\frac{8}{6}
=1+1/3
$