Question

A rectangular packet of drink has a width that is 2 cm less than its length.

Answer 1

Answer:

$6m^2+8m-16$

Step-by-step explanation:

Given that the length of the packet is $l=m$ cm.

Then the width being 2cm less than the length becomes $w=m-2$ and the height being 4 cm more than its length becomes $h=m+4$

The total surface area of the rectangular packet is given by:

$T.S.A=2(lw+lh+wh)$

$\implies T.S.A=2[m(m-2)+m(m+4)+(m-2)(m+4)]$

We expand to get:

$\implies T.S.A=2(m^2-2m+m^2+4m+m^2+4m-2m-8))$

$\implies T.S.A=2(3m^2+4m-8)=6m^2+8m-16$