surface area volume. surface area the total area of all the faces that make up a 3d shape volume the...
TRANSCRIPT
SURFACE AREA
GeometryVOLUME
GeometrySurface Area
• The total area of all the faces that make up a 3D shape
Volume• The amount of space a 3D
shape takes up.
Surface AreaRemember
• 3D shapes are a collection of 2D shapes
• Each 2D shape is a face on a 3D shape
What is Surface Area?Surface Area is the total area of all the faces
that make up a 3D shape
Think of it like finding the area of each side of a dice.
That is the dice’s surface area.
What is Surface Area?How do you find the surface area of a 3D shape?
=2
2
2 2
2
2
2
2
2
This is called a NETIt is a way of showing the 2D shapes that create a 3D shape
First you need to understand that all 3D shapes are a collection of 2D shapes
Surface AreaHow do you find the surface area of a 3D shape?
1) Split up the shape into a NET.
2
2
2
Surface AreaHow do you find the surface area of a 3D shape?
2) Divide the NET into its different faces
Surface AreaHow do you find the surface area of a 3D shape?
3) Calculate the area of each face
2m
2m
2m
2m
2m
2m
2m
2m
2m
2m
4m2
4m2
4m2
4m2
4m24m2
Surface AreaHow do you find the surface area of a 3D shape?
4) Add the area of each face.
+ 4m2 + 4m2 + 4m2 + 4m2 =+ 4m24m2
24m24m2
4m2
4m2
4m2
4m24m2
ExampleWhat is the surface area of this triangular prism?
8 in
15 in
10in
4 in
1) Split the shape into its net.2) Divide the net into its different faces.3) Calculate the area of each face.4) Add the area of each face.
Here are your steps
ExampleWhat is the surface area of this triangular prism?
1) SPLIT THE SHAPE INTO ITS NET.
8 in
15 in
10in4 in
HINT: it is always a good idea to count the number of shapes to make sure you didn’t forget any.
8 in
15 in
10in4 in
2) D IVIDE THE NET INTO ITS DIFFERENT FACES
8 in
8 in
15 in
10in4 in
4 in
4 in
8 in
8 in
15 in
10in4 in
3) CALCULATE THE AREA OF EACH FACE
8 x 15 =120 4 x 15 = 60 10 x 15 = 150
8 in
8 in
15 in
10in4 in
4 in
4 in
8 in
8(4)2
8(4)2
= 16
= 16
4) ADD THE AREA OF EACH FACE
8 x 15 =120 4 x 15 = 60 10 x 15 = 150
8 in
8 in
15 in
10in4 in
4 in
4 in
8 in
8(4)2
8(4)2
= 16
= 16
60 in2
120 in2
150 in2
16 in2
+ 16 in2
362 in2
Surface Area1)Split the shape into its net.2)Divide the net into its different faces.3)Calculate the area of each face.4)Add the area of each face.
You Try1) What is the area of this rectangular prism
5 cm
4 cm2 cm
Don’t click until you are finishedThe answer is on the next slide
Answer5 cm
4 cm2 cm
Front
Top
Back
BottomSide Side
1) Split the shape into its NET
Answer5 cm
4 cm2 cm
Front
Top
Back
Bottom
Side Side
2) Divide the NET into different faces
5 cm
5 cm
5 cm
5 cm
2 cm
2 cm 2 cm2 cm
4 cm
4 cm
4 cm4 cm
Answer5 cm
4 cm2 cm
10cm2
20cm2
10cm2
20cm2
8cm2 8cm2
3) Calculate the area of each face
5 cm
5 cm
5 cm
5 cm
2 cm
2 cm 2 cm2 cm
4 cm
4 cm
4 cm4 cm
Answer5 cm
4 cm2 cm
10cm2
20cm2
10cm2
20cm28cm2 8cm2
4) Add the area of each face 10cm2
20cm2
10cm2
20cm2
8cm2
+ 8cm2
76cm2