Question 109105
Let l=length
____w=width


IF length of a rectangle is four times its width, then {{{l=4w}}}


The perimeter,

{{{P=2l+2w}}}

becomes

{{{P=2(4w)+2w=(2*4)w+2w=8w+2w=10w}}}


But, the perimeter is 90 m . SO,

{{{10w=90}}}
{{{w=10}}}
Thus, the width measures 10 m long


again,

{{{l=4w=4*10=40}}}


Thus, the length measures 40 m long


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