Find the surface area o prisms and cylinders using

nets.

7.2 Surface Area of Prisms and Cylinders

Surface AreaUsed with 3-D figuresIs the sum of the areas of ALL its surfacesThe total area of its net

Units are squared Imagine wrapping a present, you

cover all of the surfaces. This would also give you the surface area!

Nets3-D figure

Net

ExampleFind the surface area of the following prism:

SA =2(8)5 + 2(8)4 + 2(5)4SA = 80 + 64 + 40SA = 184 cm2

CylindersFind the surface area of the following cylinder:

SA = 2(п)3(6) + 2(п)32

SA = 36п + 18пSA = 54п units2

You Try!Find the surface area of the following triangular prism:

SA = 2(½)5(12) + (12+5+13)7SA =60+ (30)7SA = 60 + 210SA = 270 units2

How Do You Find Surface Area?You can use a formula –

Cubes & Rectangular Prisms:SA = 2lw + 2lh + 2wh

Cylinders:SA = 2пrh + 2(пr2)

Triangular Prisms:SA = 2(½bh) + (perimeter)h

Perimeter is of one base face

Try This!Find the surface area of the following prism:

SA = 2lw + 2lh + 2whSA =2(7)2 + 2(7)4 + 2(2)4SA = 28 + 56 + 16SA = 100 cm2

PrcaticeFind the surface area of the following triangular prism:

SA = 2(½bh) + (perimeter)hSA =2(½)7(15) + (7+25+24)15SA = 105 + (56)15SA = 105 + 840SA = 945 units2

AssignmentOdds p. 259 #5-25