Question 1120430
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<pre>
P is given.  W is given.  L is not given.


Substitute the given values into your expression.  You will get


32 = 2*L + 2*8,   or, equivalently


32 = 2*L + 16,


32 - 16 = 2L,


16 = 2L,


L = {{{16/2}}} = 8.
</pre>

Done.


Was it hard ?