8a^2 + 40ab+ 50b^2 = 2(4a^2 +20ab +25b^2)
= 2(2a + 5b)^2
How is this a perfect square?
are you referring to
http://www.jiskha.com/display.cgi?id=1279063490 ?
Do not start a new thread, keep replying to the original.
As to your question, expand
(2a + 5b)^2 using FOIL