1. AREA OF SOLIDS

2. Area of a Prism Step 1 – Find Area of Base Abase = 8cm x 2 cm
Step 2 – Find the LA
LA = Perimeter of base x height
LA = 20 cm x 4 cm
LA = 80 cm2
Step 3 – Find TA (total area)
TA = Area of the bases + LA
TA = 2(16) cm cm 2
TA =
TA = 112 cm 2

3. Can you find the area of the base when it’s a regular polygon?
c = cote (side length)
a = apothem a
n= number of sides n
Yes…you CAN too !!!!!
Area = C A N 2

4. Example Find the area of the base of a regular hexagonal prism.
Area base = can 2
A base = 10 x 8.7 x 6
A base = 522
A base = 261 cm2
c = 10 cm
a=8.7 cm
n = 6 sides

5. Find the total surface area of this prism
Pentagonal prism that has a height of 3cm
Step 1 – Find Area 1 Base
Abase = c a n 2
Abase = 20 x 4 x 5
Abase = 400
Abase = 200cm2
Step 2 – Find the LA
LA = Pb x h
LA = (20 x 5) x 3
LA = 100 x 3
LA = 300 cm2
c = 20 cm
n = 5
a = 4 cm

6. TA prism = LA + 2(Abase) TA prism = 300 cm2 + 2 (200 cm2)
Step 3 – Find the Total Area of the prism
TA prism = LA + 2(Abase)
TA prism = 300 cm2 + 2 (200 cm2)
TA prism = 300 cm cm2
TA prism = 700 cm2
Workbook page 178 # 3,4,5

7. Answers to Workbook
Page 178 #4a) 72.72cm2 b) 108cm2 c) 190.8cm2 #5) cm2 Page 179 #6) cm2 # 7) 1107cm2 #8) 384cm2

8. Page 179 #7 Area of base = can 2 9cm Area of base = 9 x 6.2 x 5
Area of base = cm2
9cm
a= 6.2cm
LA= Pb x height
LA= (9 x 5) x 18.4
LA = 45 x 18.4
LA = 828 cm2
TA = 2(Area of base) + LA
TA = 2(139.5)
TA =
TA = 1107 cm2

9. Area of a Cylinder Step 1 – Find Area of Bases Base is a circle….
Height = 50 mm
r =10 mm
Step 1 – Find Area of Bases
Base is a circle….
Area = π r2
Abase = π(102)
Abase = mm2
Step 2 – Find the Lateral Area
LA = Circumference of base x Height
LA = 2πr x Height
LA = 2π(10) x 50
LA = x 50
LA = mm2

10. Step 3 – find the total area of the cylinder TA = LA + 2 Abase
TA = mm2
Workbook
Page 181 #14a,b,c
#15

11. Area of Pyramid Step 1 –find area of base A = L x W A = 12 x 12
Square base
12cm
Apothem
15cm
Step 1 –find area of base
A = L x W
A = 12 x 12
A = 144 cm2
Step 2 – Find LA
LA = Pb x apothem 2
LA = 48 x 15
LA = 360 cm2

12. Step 3 – Total Area TA = LA + Area of Base TA = 360 + 144 TA = 504 cm2
Workbook
Page 182 #18 to 22

13. Area of a Cone Step 1 – Find Area of Base Area of base = πr2
height
apothem = 12
radius= 4.5 cm
Step 1 – Find Area of Base
Area of base = πr2
Area of base = π (4.52)
Area of base = cm2
Step 2 – Find the LA
LA = π r x apothem
LA = π (4.5) ( 12)
LA = cm2
Workbook
Page 184 # 27-34

14. Step 3 – Find the Total Surface Area
TA = LA + Area of base
TA =
TA = cm2

15. Area of a Sphere
r = 7cm
TA = LA = 4πr2
TA = 4 π (72)
TA = cm2 r