The width of a rectangle is half the length. The perimeter is 42 cm. find the dimensions of the rectangle.

Question

I need the dimensions of the rectangle 

Answer 1

Here's what we know:

P = 2L + 2w (perimeter = the two lengths and 2 widths added together)

L = 2w (the length is twice as long as width)

P = 42 (perimeter is 42 cm)

 

Now that we have values for most of our variables, lets plug them in:

42 = 2(2w) + 2w

42 = 4w + 2w

42 = 6w

7 cm = w

 

L = 2 * 7

L = 14 cm

 

check:

42 = 14 * 2 + 7 * 2

42 = 28 + 14

42 = 42