Question 802870
In word problems, they will probably 
tell you that the length and width are
related in some way.
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They might say that the length equals
the width plus 3
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In that case, call the width {{{ x }}} and
call the length {{{ x + 3 }}}
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Then it will ask you for the area or
the perimeter
{{{ A = L*W }}}
{{{ P = 2L + 2W }}}
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Substituting for {{{ L }}} and {{{ W }}},
{{{ A = ( x + 3 )*x }}}
and
{{{ P = 2*( x + 3 ) + 2x }}}
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Then you use what else is given to find
out what they want.
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When dealing with area, they often want
to know the maximum area you can enclose
with a certain length of fence.
That always turns out to be a square area, so
the length and width would not be different
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When they are concerned with the perimeter,
they usually want to know the minimum
length of fence that will enclose a certain
area.
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Hope this helps