How do you find the sum or difference of #(2a-4a^2+1)-(5a^2-2a-6)#?

1 Answer
Dec 18, 2016

#-9a^2 + 4a + 7#

Explanation:

First, expand the terms within parenthesis paying close attentions to the signs inside and out side the parenthesis:

#2a - 4a^2 + 1 - 5a^2 + 2a + 6#

Now, group like terms:

#- 4a^2 - 5a^2 + 2a + 2a + 1 + 6#

Next combine the like terms:

#(-4 - 5)a^2 + (2 + 2)a + 7#

#-9a^2 + 4a + 7#