(4x+4)(7x-44)=39

Solution for (4x+4)(7x-44)=39 equation:

(4x+4)(7x-44)=39

We move all terms to the left:

(4x+4)(7x-44)-(39)=0

We multiply parentheses ..

(+28x^2-176x+28x-176)-39=0

We get rid of parentheses

28x^2-176x+28x-176-39=0

We add all the numbers together, and all the variables

28x^2-148x-215=0

a = 28; b = -148; c = -215;
Δ = b2-4ac
Δ = -1482-4·28·(-215)
Δ = 45984
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{45984}=\sqrt{16*2874}=\sqrt{16}*\sqrt{2874}=4\sqrt{2874}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-148)-4\sqrt{2874}}{2*28}=\frac{148-4\sqrt{2874}}{56}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-148)+4\sqrt{2874}}{2*28}=\frac{148+4\sqrt{2874}}{56}
$