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?

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