How do you factor #4a^2 + 20a + 25#?

1 Answer
Jun 26, 2015

Answer:

It is a perfect square trinomial:
#4a^2+20a+25 = (2a+5)^2#

Explanation:

The first term is the square of #2a#

The last term is the square of #5#

Multiplt those two, then doubles the number. Is that the middle term? If yes, then it is a perfect square.

#2a xx 5 = 10a#. Now double that (multiply by #2#): #2 xx 10a = 20a# Yes, that is the middle term on the original expression, so it is a perfect square,