7x^2+20x+12=1664

Solution for 7x^2+20x+12=1664 equation:

7x^2+20x+12=1664

We move all terms to the left:

7x^2+20x+12-(1664)=0

We add all the numbers together, and all the variables

7x^2+20x-1652=0

a = 7; b = 20; c = -1652;
Δ = b2-4ac
Δ = 202-4·7·(-1652)
Δ = 46656
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{46656}=216$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(20)-216}{2*7}=\frac{-236}{14}
=-16+6/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(20)+216}{2*7}=\frac{196}{14}
=14
$