28n^2=-128-144n

Solution for 28n^2=-128-144n equation:

28n^2=-128-144n

We move all terms to the left:

28n^2-(-128-144n)=0

We add all the numbers together, and all the variables

28n^2-(-144n-128)=0

We get rid of parentheses

28n^2+144n+128=0

a = 28; b = 144; c = +128;
Δ = b2-4ac
Δ = 1442-4·28·128
Δ = 6400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{6400}=80$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(144)-80}{2*28}=\frac{-224}{56}
=-4
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(144)+80}{2*28}=\frac{-64}{56}
=-1+1/7
$