(7x+3)(8x+1)=

Solution for (7x+3)(8x+1)= equation:

(7x+3)(8x+1)=

We move all terms to the left:

(7x+3)(8x+1)-()=0

We add all the numbers together, and all the variables

(7x+3)(8x+1)=0

We multiply parentheses ..

(+56x^2+7x+24x+3)=0

We get rid of parentheses

56x^2+7x+24x+3=0

We add all the numbers together, and all the variables

56x^2+31x+3=0

a = 56; b = 31; c = +3;
Δ = b2-4ac
Δ = 312-4·56·3
Δ = 289
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{289}=17$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(31)-17}{2*56}=\frac{-48}{112}
=-3/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(31)+17}{2*56}=\frac{-14}{112}
=-1/8
$