Unit 10 · Measurement and Three-Dimensional Geometry

10.5Surface Area of Prisms and Cylinders

Quick Answer

Prism: SA = 2B + Ph (2 bases + lateral area). Cylinder: SA = 2πr² + 2πrh. Both formulas add the two base areas to the lateral (side) area.

Essential Question

How does unfolding a three-dimensional solid into a net reveal the formula for its surface area?

Learning Goals

  • 1Define lateral area and total surface area.
  • 2Draw and interpret nets of prisms and cylinders.
  • 3Apply the surface area formula for right prisms.
  • 4Apply the surface area formula for right cylinders.

Key Vocabulary

Lateral area

The sum of the areas of all lateral (non-base) faces of a solid.

Net

A two-dimensional pattern that can be folded to form a three-dimensional solid.

Right prism

A prism in which the lateral edges are perpendicular to the bases.

Right cylinder

A cylinder in which the axis is perpendicular to the bases.

Full lesson content coming soon

Worked examples, guided practice problems, a workbook, quiz, and downloadable PDF resources will be added to this lesson in Phase 2. The learning goals and vocabulary above reflect the complete lesson scope.