7x(4x+4)=4(30x-6)

Solution for 7x(4x+4)=4(30x-6) equation:

7x(4x+4)=4(30x-6)

We move all terms to the left:

7x(4x+4)-(4(30x-6))=0

We multiply parentheses

28x^2+28x-(4(30x-6))=0


We calculate terms in parentheses: -(4(30x-6)), so:

4(30x-6)

We multiply parentheses

120x-24

Back to the equation:

-(120x-24)


We get rid of parentheses

28x^2+28x-120x+24=0

We add all the numbers together, and all the variables

28x^2-92x+24=0

a = 28; b = -92; c = +24;
Δ = b2-4ac
Δ = -922-4·28·24
Δ = 5776
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{5776}=76$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-92)-76}{2*28}=\frac{16}{56}
=2/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-92)+76}{2*28}=\frac{168}{56}
=3
$