perimeter, area, find unknown side length

Front

What is perimeter?

Back

Perimeter is the total distance around the outside of a shape.

Front

How do you calculate the perimeter of a rectangle?

Back

Add the lengths of all four sides or use the formula: P = 2(length + width).

Front

What is area?

Back

Area is the amount of space inside a shape, measured in square units.

Front

How do you calculate the area of a rectangle?

Back

Multiply the length by the width: Area = length × width.

Front

What is the formula for the area of a square?

Back

Area = side × side or Area = side².

Front

If the area of a rectangle is 50 square feet and the width is 10 feet, what is the length?

Back

5 feet.

Front

What is the formula for the perimeter of a square?

Back

Perimeter = 4 × side.

Front

If a square has a perimeter of 100 feet, what is the length of each side?

Back

25 feet.

Front

What is the relationship between the length and width of a rectangle when calculating area?

Back

Area = length × width; if one dimension is known, the other can be found.

Front

If an envelope is 3 inches wide with a perimeter of 30 inches, what is the length?

Back

12 inches.