-4n-56=4(2/5n-7)

Solution for -4n-56=4(2/5n-7) equation:

-4n-56=4(2/5n-7)

We move all terms to the left:

-4n-56-(4(2/5n-7))=0


Domain of the equation: 5n-7))!=0

n∈R


We multiply all the terms by the denominator


-4n*5n-56*5n-7))-(4(2-7))=0

We add all the numbers together, and all the variables

-4n*5n-56*5n-7))-(4(-5))=0

We add all the numbers together, and all the variables

-4n*5n-56*5n=0

Wy multiply elements

-20n^2-280n=0

a = -20; b = -280; c = 0;
Δ = b2-4ac
Δ = -2802-4·(-20)·0
Δ = 78400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{78400}=280$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-280)-280}{2*-20}=\frac{0}{-40}
=0
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-280)+280}{2*-20}=\frac{560}{-40}
=-14
$