Question

The length of a rectangle is 3 times its width. The rectangle’s width is 4 m. What is the area of the rectangle? Enter your answer in the box. m²

Answer 1

Answer:

48m²

Step-by-step explanation:

L= 3*4

W= 4

Area= L*W

A=(3*4)*4

A=12*4

A=48

Answer 2

Call the length $l$ and the width $w$ 

We are told:
1. "The length of a rectangle is 3 times its width." i.e.: $l=3w$
2. "The rectangle’s width is 4 m." i.e.: $w=4$

So, by substitution we have:
$l=3w$
$l=3(4)$
$l=12m$

Then we can use our area formula:
$A=lw$
$A=(12m)(4m)$
$Area=48m^{2}$