Question

A rectangle has a perimeter of 30 inches.  Its length is one less than three times its width.  What are the length and width of the rectangle?

Answer 1

Answer:

11 inches

Step-by-step explanation:

l = length of the rectangle

w = width of the rectangle

l = 3w-1  (As stated in the question)

The equation is:

2l+2w = 30

2(3w-1)+2w = 30

6w-2+2w=30

8w=32

w = 32/8

width = 4

From the width you can find the length, which is (30-2x4)/2, which is 22/2 = 11 inches

Answer 2

Perimeter of a rectangle can be represented by 2* length + 2 * width

We can represent the width with the variable x

We can represent the length by the expression 3x-1

So, now we can make a forumla and solve

2(3x-1) + 2(x) = 30

6x-2+2x = 30

8x = 32

x = 4 is the width of the rectange.

Now we find the length

3(4)-1

11 = Length