What is the answer to this

Answer: My answer would be x=1.8
Step-by-step explanation:
I got this answer by first adding 81 to both sides of the equation making the equation look like this: 25x^2 (or 25x squared) = 81. Next I divided 81 by 25 giving me x^2= 3.24. Then to reverse a square you square root both sides of the equation to get x=1.8. And to check my answer 1.8^2= 3.24 x 25= 81 - 81= 0