2(4x-3)(7x+2)=0

Solution for 2(4x-3)(7x+2)=0 equation:

2(4x-3)(7x+2)=0

We multiply parentheses ..

2(+28x^2+8x-21x-6)=0

We multiply parentheses

56x^2+16x-42x-12=0

We add all the numbers together, and all the variables

56x^2-26x-12=0

a = 56; b = -26; c = -12;
Δ = b2-4ac
Δ = -262-4·56·(-12)
Δ = 3364
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3364}=58$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-26)-58}{2*56}=\frac{-32}{112}
=-2/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-26)+58}{2*56}=\frac{84}{112}
=3/4
$