Which trinomial is not a perfect square ? #1)4x^2+ 4x+1 #2)x^2 +10x-25 or #3) 25-30x+9x^2

Question

Which trinomial is not a perfect square ? #1)4x^2+ 4x+1   #2)x^2 +10x-25 or #3) 25-30x+9x^2

anonymous · Answer

#3 is not a perfect square

anonymous · Answer

can you please show me how you got that answer?

anonymous · Answer

wait...its #2

anonymous · Answer

Because #1 factors out to (2x+1)^2 and #3 (-3x+5)^2 #2 does not factor out properly I miss read the +10 to be -10 other wise that one would have factored out to (x-5)^2 to make that one a perfect square you would need to add 50

anonymous · Answer

can you show me how you factored out #3

anonymous · Answer

First put it in proper order 9x^2-30x=25
Then Factor
(-3x+5)(-3x+5) =(-3x+5)^2

anonymous · Answer

Sometimes it helps to see it as a^2 -2ab- b^2
That would look like -9x^2+(2)(-15x)+25 or -9x^2-15x-15x+25

anonymous · Answer

mmkay  thank you soo much :)