How to find dimensions of a rectangle with a perimeter of 24m?

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1 Answer
May 31, 2018

Any lengths/widths satisfying the equation

#l+w=12#

Explanation:

We know that perimeter is given by

#2l+2w#

where #l# is the length and #w# is the width. We are saying the perimeter is equal to #24#, so we have the following equation:

#2l+2w=24#

Both terms have a #2# in common, so we can factor that out. We get

#2(l+w)=24#

Dividing both sides by #2#, we get

#l+w=12#

The length and the width must sum up to #12#. Any combinations will yield a perimeter of #24#.

If #l=8# and #w=4#, then we have

#2(8)+2(4)#

which simplifies to

#16+8=color(blue)(24)#

Notice that #8# and #4# sum up to #12#. So any combination of numbers that add up to #12# will be our dimensions.

Hope this helps!