How to Find the Area and Perimeter of a Rectangle

Step-by-Step Guide

1. 1

   Step 1: Ensure you are working with a true rectangle.

   The picture above shows a rectangle where the top and bottom lines are equal in length and the sides are equal in length.
   
   The top and bottom are parallel to each other, while the sides are also parallel to each other.
   
   In addition, the sides are perpendicular (exactly 90°) to the top and bottom lengths.If all four sides of the object are identical, then you have a square.
   
   Squares are a type of rectangle.
   
   If the object you are looking at does not meet these conditions, then it is not a rectangle.
2. 2

   Step 2: Write down the formula for the area of a rectangle

   The units for area can be any unit for the measure of length squared: feet squared, meters squared, centimeters squared, etc.
   
   You will see the units written as ft2, m2, cm2, etc. , The length of the rectangle is equal to the top or bottom of the rectangle.
   
   The width is equal to the side of the rectangle.
   
   Using a ruler, measure each side of the rectangle to determine the length and the width.
   
   In the above example, the length is 5 cm and the width is 2 cm. , Using the length and width you just measured, plug them into the formula to solve for the area.
   
   Multiply the length times the width to calculate area.
   
   For example, A = l x w = 5 x 2 = 10 cm2. , The picture above shows a rectangle where the top and bottom lines are equal in length and the sides are equal in length.
   
   The top and bottom are parallel to each other, while the sides are also parallel to each other.
   
   In addition, the sides are perpendicular (exactly 90°) to the top and bottom lengths.
   
   If all four sides of the object are identical, then you have a square.
   
   Squares are a type of rectangle.
   
   If the object you are looking at does not meet these conditions, then it is not a rectangle. , You might also see the formula written as P = 2l + 2w.
   
   This is the same formula written in a slightly different way.
   
   The units for perimeter can be any unit for the measure of length: feet, miles, meters, centimeters, etc. , The length of the rectangle is equal to the top or bottom of the rectangle.
   
   The width is equal to the side of the rectangle.
   
   Using a ruler, measure each side of the rectangle to determine the length and the width.
   
   In the above example, the length is 5 cm and the width is 2 cm. , Using the length and width you just measured, plug them into the formula to solve for the perimeter.
   
   There are two ways to solve the equation depending on which formula you have used.
   
   For P = 2(l +w) , add the length and the width together and multiply by
   2.
   
   For P = 2l + 2w, multiply the length by 2 and the width by 2, then add these products together.
   
   For example, P = 2(l + w) = 2(2 + 5) = 2(7) = 14 cm.
   
   For example, P = 2l + 2w = (2 x 2) + (2 x 5) = 4 + 10 = 14 cm.
3. 3

   Step 3: A = l x w.In the formula for area (A)

4. 4

   Step 4: l is the length and w is the width of the rectangle.

5. 5

   Step 5: Identify the length and the width of the rectangle.

6. 6

   Step 6: Plug in the variables and solve the equation.

7. 7

   Step 7: Ensure you are working with a true rectangle.

8. 8

   Step 8: Write down the formula for the perimeter of a rectangle

9. 9

   Step 9: P = 2(l + w).In the formula for the perimeter (P) of a rectangle

10. 10

    Step 10: l is the length and w is the width.

11. 11

    Step 11: Identify the length and the width of the rectangle.

12. 12

    Step 12: Plug in the variables and solve the equation.

Detailed Guide

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