1. HOW TO CALCULATE SURFACE AREA

2. SURFACE AREA
Surface area is the sum of the areas of all the faces of a solid.

3. Surface Area of a Rectangular Prism
5 cm
4 cm
10 cm

4. Surface Area of a Rectangular Prism
TOP
5 cm
SIDE
FRONT
4 cm
10 cm

5. Surface Area of a Rectangular Prism
TOP
5 cm
SIDE
FRONT
4 cm
10 cm
Area of top and bottom A=LW A=10x4 = 40 x 2 = 80cm2

6. Surface Area of a Rectangular Prism
TOP
5 cm
SIDE
FRONT
4 cm
10 cm
Area of top and bottom A=LW A=10x4 = 40 x 2 = 80cm2
Area of front and back x5 = 50 x 2 = 100cm2

7. Surface Area of a Rectangular Prism
TOP
5 cm
SIDE
FRONT
4 cm
10 cm
Area of top and bottom A=LW A=10x4 = 40 x 2 = 80cm2
Area of front and back x5 = 50 x 2 = 100cm2
Area of sides
4x5 = 20 x 2 = 40cm2

8. Surface Area of a Rectangular Prism
TOP
5 cm
SIDE
FRONT
4 cm
10 cm
Area of top and bottom A=LW A=10x4 = 40 x 2 = 80cm2
Area of front and back
10x5 = 50 x 2 = 100cm2
Area of sides
4x5 = 20 x 2 = 40cm2
SURFACE AREA
220cm2

9. Ex 1: Find the S.A. Rectangular Prism
5 cm
3 cm
21 cm

10. Find the surface area 5 cm 3 cm 21 cm Top and bottom
21x3 = 63 x 2 = 126cm2
Front and back
21x5 = 105 x 2 = 210cm2
Sides
3x5 = 15 x 2 = 30cm2
________
SURFACE AREA
366cm2

11. SA: L.A.+ 2B (L.A.=perimeter of the base(height)
Triangular Prism
SA: L.A.+ 2B (L.A.=perimeter of the base(height)
SA:( )(10)+ 2(1/2(16)(12))
SA:
SA: 672cm2

12. Ex 2: Find the S.A. of the Triangular Prism

13. Answer: SA: L.A.+ 2B S.A: (3+4+5)(11) + 2(1/2(3)(4))
S.A: =144 cm2

14. Sphere
SA: 4пr2
SA:4(3.14)(10)2
SA: 1256cm2

15. Example 3: Find the S.A of the Sphere

16. Answer:
S.A: 4пr2
S.A: 4(3.14)(5)2
S.A: 314units2

17. Cone
SA:(3.14) (4)(6)
SA:
SA: units2

18. Example 4: Find the S.A of the Cone

19. Answer: SA: пrl + пr2 S.A: 3.14(5)(13) + 3.14(5)2
S.A: = m2

20. Pyramid
SA: n(1/2(b)(l)) + B
SA:4(1/2)(6)(8) + 62
S.A:

21. Example 5: Find the S.A of the Pyramid

22. Answer: SA: n(1/2(b)(l)) + B S.A: 4(1/2(10)(18) + 102
S.A: =460 cm2

23. Cylinder S.A: 2пrh + 2пr2 S.A: 2(3.14)(5)(10) + 2(3.14)(5)2
S.A: = 471m2

24. Example 6: Find the S.A of the Cylinder

25. Answer: S.A: 2пrh + 2пr2 S.A: 2(3.14)(4)(9) + 2(3.14)(4)2
S.A: = m2