How do you multiply and simplify #\frac { 3r - 27} { r - 9} \cdot \frac { r + 7} { 3}#?
1 Answer
Apr 13, 2017
Explanation:
The first step is to
#color(blue)"factorise and cancel"# any common factors.
#rArr(3(r-9))/(r-9)xx(r+7)/3larrcolor(red)" common factor of 3"#
#=(cancel(3)^1cancel((r-9))^1)/cancel((r-9))^1xx(r+7)/cancel(3)^1larrcolor(red)" cancelling"#
#=r+7#
