SOLUTION: factor the polynomial completely,clearly show the GCF 25x² + 36y² My answer is NF

factor the polynomial completely,clearly show 
the GCF 
25x2 + 36y2 
My answer is NF

And you are right!  If the sign between them 
had been - instead of +, it would have been 
factorable.

An interesting note:

Oftentimes teachers and textbooks falsely 
say that the sum of two perfect squares can 
NEVER be factored.

However some sums of perfect squares CAN be 
factored. It's just that in general they 
cannot be.  But there are exceptions.

Here are a couple of them:

1.

x4 + 4 

is the sum of two squares, as it can 
be written as

(x2)2 + (2)2

However it is factorable as

(x2 - 2x + 2)(x2 + 2x + 2)

2.

x6 + 1 

is the sum of two squares, as it can 
be written 

(x3)2 + (1)2

However
it is factorable as 

(x2 + 1)(x4 - x2 + 1)

I just thought you might find that interesting in case
either your teacher or textbook author tells you the 
falsehood that sums of two squares are NEVER factorable.

Edwin