How to Find the Perimeter of a Rectangle

Step-by-Step Guide

1. 1

   Step 1: Write down the basic formula for finding the perimeter of a rectangle.

   This formula will help guide you as you calculate the perimeter of your own rectangle.
   
   The basic formula is:
   P = 2 * (l + w).Perimeter is always the total distance around the outside edge of any shape, whether it is simple or compound.
   
   In this equation, P stands for “perimeter,” l refers to the length of the rectangle, and w refers to the width of the rectangle.
   
   Length always has a greater value than width.
   
   Because opposite sides of a rectangle are equal, both lengths will be the same and both widths will be the same.
   
   This is why you write the equation as a multiplication of the sum of the length and width by
   2.
   
   You can also write the equation as P = l + l + w + w to make this very clear.
2. 2

   Step 2: Find the length and the width of your rectangle.

   For a basic math problem at school, the length and width of the rectangle will be provided in the problem.
   
   These are usually next to the figure of the rectangle.
   
   If you are calculating the perimeter of a rectangle in real life, use a ruler, yardstick, or tape measure to find the length and width of the area that you are trying to measure.
   
   If you’re measuring outdoors, measure all sides to see if the opposites are truly congruent.
   
   For example, l = 14 centimeter (5.5 in), w = 8 centimeter (3.1 in). , When you are working out your perimeter equations, note that according to the order of operations, mathematical expressions contained inside brackets or parentheses are solved before those outside of the parentheses.So, you’ll begin solving your equation by adding the length and width.
   
   For example, P = 2 * (l + w) = 2 * (14 + 8) = 2 * (22). , When you’re looking the formula for the perimeter of a rectangle, the “(l + w)” is multiplied by two.
   
   Once you’ve completed this multiplication, you have the perimeter of your rectangle.
   
   This multiplication takes into account the other two sides of your rectangle.
   
   When you added together the width and length, you only added together two sides of the shape.
   
   Since the other two sides of the rectangle are equal to the two already added together, you can simply multiply this measurement by two in order to find the total sum of all four sides.
   
   For example, P = 2 * (l + w) = 2 * (14 + 8) = 2 * (22) = 44 centimeter (17.3 in). , If you struggle with the concept of perimeter, this is a great place to start.
   
   For example, P = l + l + w + w = 14 + 14 + 8 + 8 = 44 centimeter (17.3 in).
3. 3

   Step 3: Add the length and width.After you identify your length and width

4. 4

   Step 4: you want to plug them into the “l” and “w” slots in the perimeter equation.

5. 5

   Step 5: Multiply the sum of the length and width by two.

6. 6

   Step 6: Add l + l + w + w. Instead of adding two sides of your rectangle and multiplying by two

7. 7

   Step 7: you can simply add all four sides together directly to find the perimeter of your rectangle.

Detailed Guide

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