width = 2n+8
length = 3 * width = 3*(2n+8) = 6n+24
Perimeter = 2(l+w)
= 2( 6n+24 + 2n+8)
= 2( 8n+32)
96 = 16n +64
-64 -64
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32 = 16n divide by `16
2 = n
width = 2n+8 = 2*n + 8= 4 + 8 = 12
length = 3*width = 3*12 = 36