134=(5x+4)(7x-2)

Solution for 134=(5x+4)(7x-2) equation:

134=(5x+4)(7x-2)

We move all terms to the left:

134-((5x+4)(7x-2))=0

We multiply parentheses ..

-((+35x^2-10x+28x-8))+134=0


We calculate terms in parentheses: -((+35x^2-10x+28x-8)), so:

(+35x^2-10x+28x-8)

We get rid of parentheses

35x^2-10x+28x-8

We add all the numbers together, and all the variables

35x^2+18x-8

Back to the equation:

-(35x^2+18x-8)


We get rid of parentheses

-35x^2-18x+8+134=0

We add all the numbers together, and all the variables

-35x^2-18x+142=0

a = -35; b = -18; c = +142;
Δ = b2-4ac
Δ = -182-4·(-35)·142
Δ = 20204
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:

$\sqrt{\Delta}=\sqrt{20204}=\sqrt{4*5051}=\sqrt{4}*\sqrt{5051}=2\sqrt{5051}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-18)-2\sqrt{5051}}{2*-35}=\frac{18-2\sqrt{5051}}{-70}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-18)+2\sqrt{5051}}{2*-35}=\frac{18+2\sqrt{5051}}{-70}
$