is 9x^2-36x+25 a perfect square?

Question

the answer is no

Answer 1

9X^2 - 36X + 25.
Test it by taking the sqrt of the
first and last term, place them in
a parenthesis and follow procedure
for removing parenthesis:

( 3X - 5 )^2 = 9X^2 - 90X + 25,
It didn't pass the test; the 2nd
term is wrong. No, it is not a
perfect square

Let's test another one:
X^2 + 10X + 25

( X + 5 )^2 = X^2 + 10X + 25.
This is a perfect square.