Date post: | 24-Dec-2015 |
Category: |
Documents |
Upload: | irene-carroll |
View: | 217 times |
Download: | 3 times |
Quiz-Warm Up! Remember 5 minutes only!Fill in the graphic organizer using what you learned yesterday.
Finding Surface Area
Step 1: Flatten the 3-D figure
A rectangular prism will flatten to 6 rectangles.
Depending on the dimensions of the 3-D figure, you will have different size rectangles.
Rectangular Prism
Finding Surface AreaStep 2: Transfer the dimensions to the 3-D figure
Dimensions: Length – 12 (the longest side) Height – 8 (top to bottom) Width – 4 (front to back)
Rectangular Prism
Height 8
Length12
Width4
Finding Surface Area
Step 3: Transfer the dimensions from the 3-D figure to the flattened figure
Dimensions: Length – 12 (the longest side) Height – 8 (top to bottom) Width – 4 (front to back)
Rectangular Prism
Height 8
Length12
Width4
8
88
12
12
12
4
4
4
4
Finding Surface AreaStep 4: Find the AREA for each rectangle. (Length X Width)
Rectangular Prism
Height 8
Length12
Width 4
8
8 8
12
12
12
4
4
4
4
12 x 4
12 x 8
12 x 4
12 x 88 x 4 8 x 4
48 sq units
96 sq units
48 sq units
96 sq units32 32
Finding Surface AreaStep 4: Find the TOTAL SURFACE AREA for the 3-D Figure
Add together the areas for each rectangle
Rectangular Prism
8
124
48 sq units
96 sq units
48 sq units
96 sq units32 32
4848
9696
3232
= 352 sq. unitsTotal surface area
Cube or SquareUse the four-step process to find the surface area of the cube.
5 m5 m
Step 1: Flatten (already done)
Step 2: Transfer numbers
Step 3: Find area of each face
Step 4: Find total area
Triangular Prism
A triangular prism will flatten to 3 rectangles and two equal triangles.
Step 1: Flatten the 3-D figure
Triangular Prism
The 2 triangles will form a rectangle
6
4
126
12
4
10
10
10
6
4
Step 2: Transfer the dimensions to the 3-D Figure
Dimension:
Base = 4
Height = 6
Hypotenuse = 12
Length = 10
Triangular Prism
6
4
126
12
4
10
10
10
10
10
10
10
6
4
12
Transfer dimensions to Flattened Figure
Step 3:
4
6
Triangular Prism
8
6
108
10
6
15
15
15
15
15
15
15
8
6
10Find the area for each rectangle and triangle
Step 4:
8
6Step 5:
Write the area inside the specific shape
A = 8 x 15
A = 10 x 15
A = 6 x 15
120
150
90
A = 6 x 8
2 24 24
Triangular Prism
8
6
108
10
6
15
15
15
15
15
15
15
8
6
10Add all the areas for the total surface area
Step 6:
8
6
120
150
90
24 24
90
120150
2424
408 =Total surface
area
Cylinder
A Cylinder will flatten to a rectangle and two equal circles.
Step 1: Flatten the 3-D shape
Cylinder Step 2: Transfer the dimensions to the 3-D shape
Height - 15Diameter - 8
Formulas to use:
A =
15
Height
Diameter8
r = d 2
Height15
r = 4
Diameter = 8
2Π4 = 8Π
25
radius4
Step 3: Transfer dimensions to the flattened shape
8Π = 25
Length =
15
Cylinder Step 4: Find the area for each shape
25
15
8
15
8
4
3.14 x 4 x 4 = 50A = 50
A = 50
A = 375
25 x 15
Step 5: Add the areas for the shapes
5050
375
425 = Total surface area