-7n(n+2)=-14-7n

Solution for -7n(n+2)=-14-7n equation:

-7n(n+2)=-14-7n

We move all terms to the left:

-7n(n+2)-(-14-7n)=0

We add all the numbers together, and all the variables

-7n(n+2)-(-7n-14)=0

We multiply parentheses

-7n^2-14n-(-7n-14)=0

We get rid of parentheses

-7n^2-14n+7n+14=0

We add all the numbers together, and all the variables

-7n^2-7n+14=0

a = -7; b = -7; c = +14;
Δ = b2-4ac
Δ = -72-4·(-7)·14
Δ = 441
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{441}=21$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-7)-21}{2*-7}=\frac{-14}{-14}
=1
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-7)+21}{2*-7}=\frac{28}{-14}
=-2
$