(6x+-7)(7/8x+3)=0

Solution for (6x+-7)(7/8x+3)=0 equation:

(6x+-7)(7/8x+3)=0


Domain of the equation: 8x+3)!=0

x∈R


We add all the numbers together, and all the variables

(6x-7)(7/8x+3)=0

We multiply parentheses ..

(+42x^2+18x-49x-21)=0

We get rid of parentheses

42x^2+18x-49x-21=0

We add all the numbers together, and all the variables

42x^2-31x-21=0

a = 42; b = -31; c = -21;
Δ = b2-4ac
Δ = -312-4·42·(-21)
Δ = 4489
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4489}=67$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-31)-67}{2*42}=\frac{-36}{84}
=-3/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-31)+67}{2*42}=\frac{98}{84}
=1+1/6
$