Question

The length of a rectangle is 1 more than 3 times the width . If the perimeter of the rectangle is 18 units , what’s it’s area?

Answer 1

Answer:

14 square units

Step-by-step explanation:

You need to know the formulas for the perimeter of a rectangle and the area of a rectangle, which are

2L + 2W - P     where L is the length, W is the width, and P is the perimeter

and

A = LW      

So we need to find the length and width to find the area

Step 1:  Write equations out of the given information

"The length of a rectangle is 1 more than 3 times the width" can be rewritten as

L = 3W + 1

"the perimeter of the rectangle is 18 units" can be rewritten as

2L + 2W = 18

Step 2:  Plug the first formula into the second one and solve

      2(3W + 1) + 2W = 18

Simplify...

      6W + 2 + 2W = 18

Combine like terms and subtract 2 from both sides

     8W = 16

Divide both sides by 8 to isolate the W

   W = 2

Step 3:  

Plug W = 2 into the formula for L and solve for L

  L = 3(2) + 1

      L = 6 + 1

        L = 7

Step 4:  Use the length and width to calculate the area

A = LW

  A = (7)(2)

     A = 14 units squared