the length of rectangle

Question

The length of a rectangle is
4
times the width. If the area is
144
square feet, then what is the length of the rectangle, in feet?

Answer 1

To begin, recall the equation for the area of a rectangle: A= lw, where l is the length and w is the width.

 

We are given the condition that the length is 4 times the width which can be written as this: l= 4w.

 

So, we can substitute 4w into the area equation: A= (4w)w or A=4w²

 

Now we can begin the math since we know the area:

 

144 ft²=4w²

36 ft²= w²

√(36 ft²)=√w²

6 ft = w

 

Now we know the width, and can plug it back into the first condition of l=4w

 

l= 4*6 ft

l= 24 ft