X^2=0.04x+18^2

Solution for X^2=0.04x+18^2 equation:

X^2=0.04X+18^2

We move all terms to the left:

X^2-(0.04X+18^2)=0

We get rid of parentheses

X^2-0.04X-18^2=0

We add all the numbers together, and all the variables

X^2-0.04X-324=0

a = 1; b = -0.04; c = -324;
Δ = b2-4ac
Δ = -0.042-4·1·(-324)
Δ = 1296.0016
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-0.04)-\sqrt{1296.0016}}{2*1}=\frac{0.04-\sqrt{1296.0016}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-0.04)+\sqrt{1296.0016}}{2*1}=\frac{0.04+\sqrt{1296.0016}}{2}
$