Chapter 11.4 Volumes of Prisms and Cylinders

Finding the Volume of a rectangular prism

Vocabulary Volume = the space that a figure occupies. It is measured in cubic units.

Cavalieri’s Principle If two space figures have the same height and the same cross-sectional area at every level, then they have the same volume

Volume of a Prism The volume of a prism is the product of the area of a base and the height of the prism

Example #1 Find the volume of the rectangular prism

Ex. 2: Finding Volumes A = ½ bh Area of a triangle A = ½ (3)(4) Find the volume of the right prism. A = ½ bh Area of a triangle A = ½ (3)(4) Substitute values A = 6 cm2 Multiply values -- base V = Bh Volume of a prism formula V = (6)(2) Substitute values V = 12 cm3 Multiply values & solve

Example #2 Find the volume of the triangular prism Which Surface is the Base of the prism? What is the Height of the prism?

Volume of a Cylinder The volume of a cylinder is the product of the area of the base and the height of the cylinder

Ex. 2: Finding Volumes A = r2 Area of a circle A = 82 Find the volume of the right cylinder. A = r2 Area of a circle A = 82 Substitute values A = 64 in.2 Multiply values -- base V = Bh Volume of a prism formula V = 64(6) Substitute values V = 384in.3 Multiply values & solve V = 1206.37 in.3 Simplify

Example #3 Find the volume of the cylinder

Classwork 11.4 Volumes of Prisms and Cylinders