5x2=28x+12

Solution for 5x2=28x+12 equation:

5x^2=28x+12

We move all terms to the left:

5x^2-(28x+12)=0

We get rid of parentheses

5x^2-28x-12=0

a = 5; b = -28; c = -12;
Δ = b2-4ac
Δ = -282-4·5·(-12)
Δ = 1024
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1024}=32$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-28)-32}{2*5}=\frac{-4}{10}
=-2/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-28)+32}{2*5}=\frac{60}{10}
=6
$