Perimeter: Missing Sides (3.7B)

Front

What is perimeter?

Back

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

Front

How do you find the perimeter of a rectangle?

Back

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

Front

If one side of a rectangle is 5m and the other is 3m, what is the perimeter?

Back

P = 2(5m + 3m) = 16m.

Front

What is the formula for the perimeter of a square?

Back

P = 4 × side length.

Front

If the perimeter of a square is 20m, what is the length of one side?

Back

Side length = 20m ÷ 4 = 5m.

Front

What is a missing side in a perimeter problem?

Back

A missing side is a side length that you need to find in order to calculate the total perimeter.

Front

If the perimeter is 44m and one side is 20m, what is the length of the missing side?

Back

Missing side = 44m - 20m - 20m = 4m.

Front

What do you do if you know the perimeter and one side length?

Back

Subtract the known side length from the total perimeter to find the sum of the other sides.

Front

What is the perimeter of a triangle with sides 3m, 4m, and 5m?

Back

P = 3m + 4m + 5m = 12m.

Front

If a rectangle has a perimeter of 34cm and one side is 6cm, what is the other side?

Back

Other side = (34cm - 2 × 6cm) ÷ 2 = 11cm.