Download - Warm Up
Warm UpFind the surface area of the following figures. Show work and include units!
1. 2.
3. 4.
3.84 mm
12.25 in4.19 in
9 ft
6.57 ft5.28 ft
19 ft
Lesson 5-2:Surface Area of
Triangular Prisms and Cylinders
I can…• find the surface area of a triangular prism.• find the surface area of a cylinder.
Vocabulary•Cylinder
Surface Area (REVIEW)
The total area of the surface of a three dimensional object
*We will use nets to help us determine the surface area
Net (REVIEW)
A two-dimensional figure that can be folded on its segments or curved on its boundaries to form a three-dimensional figure.
Right Prism (REVIEW)A prism that
has two bases, one directly above the other, and has its lateral faces as rectangles.
Triangular Prism
A prism whose bases are triangles.
Video Over Surface Area of a Triangular Prism» http://
www.youtube.com/watch?v=yHtdtsOWnDI
Surface Area of a Triangular Prism
» First, let’s draw a net of a triangular prism.
7 cm
Triangle 1 = (½*b*h) Triangle 2 = (½*b*h) = (½*8*10)
= (½*80) = 40 sq. cm
= (½*8*10)
= (½*80) = 40 sq. cm
Surface Area of a Triangular Prism
7 cm
Rectangle 1= (l * w) Rectangle 3 = ( l * w)
=(7 * 60)
= 420 sq. cm
= ( 8 * 60)
= 480 sq. cm
Rectangle 2= (l * w)
=(7 * 60)
= 420 sq. cm
Surface Area of a Triangular Prism
7 cm
Total Surface Area = Area of Triangles + Area of Rectangles
= 40 + 40 + 420 + 420 + 480= 1400 sq. cm
Examples
» What is the surface area of the triangular prism?
Triangle 1 SA= 12 sq. metersTriangle 2 SA= 12 sq. meters Rectangle 1 SA= 63 sq. meters Rectangle 2 SA= 56 sq. meters
9 m
Rectangle 3 SA= 21 sq. metersTotal = 164 sq. meters
Cylinder» A three dimensional shape with two
identical flat ends that are circular or elliptical connected by a curved surface.
Surface Area of a Cylinder
The net of a cylinder:
Video Over Surface Area of a Cylinder
» http://www.youtube.com/watch?v=GpHhvuRbB-8