Find the product?

#(a-9)^2#

1 Answer
Mar 21, 2018

#a^2-18a+81#

Explanation:

#(a-9)^2=(a-9)(a-9)#

#"each term in the second factor is multiplied by each"#
#"term in the first factor"#

#rArr(color(red)(a-9))(a-9)#

#=color(red)(a)(a-9)color(red)(-9)(a-9)larrcolor(blue)"distribute"#

#=(color(red)(a)xxa)+(color(red)(a)xx-9)+(color(red)(-9)xxa)+(color(red)(-9)xx-9)#

#=a^2-9a-9a+81larrcolor(blue)"collect like terms"#

#=a^2-18a+81#