(7x+3)(9x-1)=0

Solution for (7x+3)(9x-1)=0 equation:

(7x+3)(9x-1)=0

We multiply parentheses ..

(+63x^2-7x+27x-3)=0

We get rid of parentheses

63x^2-7x+27x-3=0

We add all the numbers together, and all the variables

63x^2+20x-3=0

a = 63; b = 20; c = -3;
Δ = b2-4ac
Δ = 202-4·63·(-3)
Δ = 1156
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1156}=34$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(20)-34}{2*63}=\frac{-54}{126}
=-3/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(20)+34}{2*63}=\frac{14}{126}
=1/9
$