How do you factor #9-(k+3)^2#?
1 Answer
May 2, 2017
Explanation:
This expression is a
#color(blue)"difference of squares"# which factorises in general as.
#color(red)(bar(ul(|color(white)(2/2)color(black)(a^2-b^2=(a-b)(a+b))color(white)(2/2)|)))#
#"for " 9-(k+3)^2#
#a=3" and " b=k+3#
#rArr9-(k+3)^2=(3-(k+3))(3+(k+3))#
#color(white)(rArr9-(k+3)^2)=(3-k-3)(6+k)#
#color(white)(rArr9-(k+3)^2)=-k(6+k)#