Area, Perimeter, & Circumference

Front

What is the formula for the area of a triangle?

Back

A = ½bh

Front

What is the area of a shape with a base of 30 inches and a height of 28 inches?

Back

A = ½(30)(28) = 420 in²

Front

What is the area of a rectangle with a length of 10 ft and a width of 5 ft?

Back

A = lw = 10 ft × 5 ft = 50 ft²

Front

What does perimeter mean?

Back

The distance around the shape.

Front

What is the formula for the perimeter of a rectangle?

Back

P = 2(l + w)

Front

If a square has a side length of 4 inches, what is its perimeter?

Back

P = 4 × 4 = 16 inches

Front

What is the formula for the circumference of a circle?

Back

C = πd or C = 2πr

Front

If the radius of a circle is 7 inches, what is its circumference?

Back

C = 2π(7) ≈ 43.98 inches

Front

What is the relationship between diameter and radius?

Back

Diameter = 2 × Radius

Front

If the diameter of a circle is 20 inches, what is the radius?

Back

Radius = 20 inches ÷ 2 = 10 inches