Question 326199
{{{A1=L*W=21}}}
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{{{A2=(L+2)(W+2)}}}
{{{A2=LW+2L+2W+4}}}
{{{A2=21+2L+2W+3}}}
{{{A2=24+2(L+W)}}}
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For the new area, you need to have the original length and width.
{{{A2=24+2(L+W)}}}