How do you simplify #\frac { 18- 6k } { 6k - 18} \div \frac { 1} { k + 5}#?

1 Answer
Aug 29, 2017

#-k-5#

Explanation:

Factorise as far as possible first.

#(18-6k)/(6k-18) div 1/(k+5)#

#=(cancel6color(red)((3-k)))/(cancel6(k-3))div 1/(k+5)#

#=color(red)(-(k-3))/((k-3)) xx (k+5)/1" "larr# note sign change

#=(-cancel((k-3)))/(cancel((k-3))) xx (k+5)/1#

#=-(k+5)#

#=-k-5#