(4x-28)(x+11)=

Solution for (4x-28)(x+11)= equation:

(4x-28)(x+11)=

We move all terms to the left:

(4x-28)(x+11)-()=0

We add all the numbers together, and all the variables

(4x-28)(x+11)=0

We multiply parentheses ..

(+4x^2+44x-28x-308)=0

We get rid of parentheses

4x^2+44x-28x-308=0

We add all the numbers together, and all the variables

4x^2+16x-308=0

a = 4; b = 16; c = -308;
Δ = b2-4ac
Δ = 162-4·4·(-308)
Δ = 5184
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{5184}=72$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(16)-72}{2*4}=\frac{-88}{8}
=-11
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(16)+72}{2*4}=\frac{56}{8}
=7
$