2c^2=5c^2+18c

Solution for 2c^2=5c^2+18c equation:

2c^2=5c^2+18c

We move all terms to the left:

2c^2-(5c^2+18c)=0

We get rid of parentheses

2c^2-5c^2-18c=0

We add all the numbers together, and all the variables

-3c^2-18c=0

a = -3; b = -18; c = 0;
Δ = b2-4ac
Δ = -182-4·(-3)·0
Δ = 324
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$c_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$c_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{324}=18$
$c_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-18)-18}{2*-3}=\frac{0}{-6}
=0
$
$c_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-18)+18}{2*-3}=\frac{36}{-6}
=-6
$