3948=(7x+10)(4x-6)

Solution for 3948=(7x+10)(4x-6) equation:

3948=(7x+10)(4x-6)

We move all terms to the left:

3948-((7x+10)(4x-6))=0

We multiply parentheses ..

-((+28x^2-42x+40x-60))+3948=0


We calculate terms in parentheses: -((+28x^2-42x+40x-60)), so:

(+28x^2-42x+40x-60)

We get rid of parentheses

28x^2-42x+40x-60

We add all the numbers together, and all the variables

28x^2-2x-60

Back to the equation:

-(28x^2-2x-60)


We get rid of parentheses

-28x^2+2x+60+3948=0

We add all the numbers together, and all the variables

-28x^2+2x+4008=0

a = -28; b = 2; c = +4008;
Δ = b2-4ac
Δ = 22-4·(-28)·4008
Δ = 448900
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{448900}=670$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(2)-670}{2*-28}=\frac{-672}{-56}
=+12
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+670}{2*-28}=\frac{668}{-56}
=-11+13/14
$