What is the equation for the perimeter of any rectangle whose width is 8 cm less than its length?

##(4x-16)cms##
Let the length be ##color(red)(x##
Then
The width will be written as ##color(red)(x-8##
(Width of rectangle is ##8cm## less than length )
Perimeter of rectangle=##color(blue)(2(l+b)units##
SoSubstitute ##color(red)(x## and ##color(red)(x-8##
##rarr2(color(red)((x)+(x-8)))##
Remove brackets
##rarr2(color(red)(x+x-8))##
##rarr2(color(red)(2x-8))##
Use distributive property ##color(brown)(a(b+c)=ab+ac##
##rArrcolor(green)(=4x-16cms##