25a^2=216

Solution for 25a^2=216 equation:

25a^2=216

We move all terms to the left:

25a^2-(216)=0

a = 25; b = 0; c = -216;
Δ = b2-4ac
Δ = 02-4·25·(-216)
Δ = 21600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{21600}=\sqrt{3600*6}=\sqrt{3600}*\sqrt{6}=60\sqrt{6}$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-60\sqrt{6}}{2*25}=\frac{0-60\sqrt{6}}{50}
=-\frac{60\sqrt{6}}{50}
=-\frac{6\sqrt{6}}{5}
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+60\sqrt{6}}{2*25}=\frac{0+60\sqrt{6}}{50}
=\frac{60\sqrt{6}}{50}
=\frac{6\sqrt{6}}{5}
$