How do you multiply #(7a^4+2a^2)(a-5)#?

1 Answer
May 27, 2017

#color(blue)(7a^5-35a^4+2a^3-10a^2#

Explanation:

#color(white)(aaaaaaaaaaaaa)##7a^4+2a^2#
#color(white)(aaaaaaaaaaa)## xx underline(a-5)#
#color(white)(aaaaaaaaaaaaa)##7a^5+2a^3#
#color(white)(aaaaaaaaaaaaaaaaaaaaaa)##-35a^4-10a^2#
#color(white)(aaaaaaaaaaaaa)##overline(7a^5+2a^3-35a^4-10a^2)#

arrange the terms in decreasing power:

#color(blue)(7a^5-35a^4+2a^3-10a^2#