(15x)2=300

Solution for (15x)2=300 equation:

(15x)2=300

We move all terms to the left:

(15x)2-(300)=0

We add all the numbers together, and all the variables

15x^2-300=0

a = 15; b = 0; c = -300;
Δ = b2-4ac
Δ = 02-4·15·(-300)
Δ = 18000
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{18000}=\sqrt{3600*5}=\sqrt{3600}*\sqrt{5}=60\sqrt{5}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-60\sqrt{5}}{2*15}=\frac{0-60\sqrt{5}}{30}
=-\frac{60\sqrt{5}}{30}
=-2\sqrt{5}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+60\sqrt{5}}{2*15}=\frac{0+60\sqrt{5}}{30}
=\frac{60\sqrt{5}}{30}
=2\sqrt{5}
$