1. QuestionsWolf

1. Calculate the surface area of this triangular prism. a. 255 m^2 b. 360 m^2 c. 468 m^2 d. 495 m^2

2. sauravshakya

Did u mean Total Surface Area?

3. QuestionsWolf

Yes.

4. sauravshakya

First Try to find the base of the right angled triangle

5. QuestionsWolf

Is the formula SA =2B +(s1+s2+s3)h

6. sauravshakya

Use pythagorean theorem

7. QuestionsWolf

How would I do that?

8. sauravshakya

|dw:1362320690928:dw| then, 9^2 +x^2 =15^2

9. SeanAcedia

caCan't you just use the fact that the 12m on the bottom is parallel to the leg on the top?

10. sauravshakya

Oh yes! u can use it

11. QuestionsWolf

I still don't get it.

12. sauravshakya

Now, u can directly use the formula mentioned above

13. QuestionsWolf

But I don't know what the base is.

14. sauravshakya

It is 12

15. sauravshakya

So, Find the Area of the Base

16. QuestionsWolf

Okay. how do we do that?

17. sauravshakya

Area of traingle =1/2 base * height

18. QuestionsWolf

so 6 * 10.

19. sauravshakya

No

20. QuestionsWolf

Then what is the height?

21. sauravshakya

Base of the triangle is 12 and height is 9

22. QuestionsWolf

so 6 * 9 = 54

23. QuestionsWolf

54 is our base now?

24. sauravshakya

Yes, thats the Area of the right angled triangle base

25. QuestionsWolf

So SA =2(54) +(s1+s2+s3)h

26. sauravshakya

Now, Total Surface Area = 2* Area of base +(s1+s2+s3) * height of the prism

27. QuestionsWolf

The height of the prism is 10.

28. sauravshakya

yes

29. QuestionsWolf

SA =2(54) +(s1+s2+s3)10

30. QuestionsWolf

How do we find the sides?

31. sauravshakya

The sides are 9 , 12 and 15

32. sauravshakya

Observe the figure

33. QuestionsWolf

So, SA =2(54) +(9+12+15)10

34. sauravshakya

very correct

35. QuestionsWolf

36. sauravshakya

\[\checkmark\]

37. QuestionsWolf

Thank you. Do you think you can help me with two more?

38. sauravshakya

welcome

39. SeanAcedia

Basically to find the surface area you would need to find the area of each individual 2 dimensional shape and add them together.

40. QuestionsWolf

2. What is the approximate length of the lateral surface for the cylinder shown here in net form? a. 31.4 in b. 62.8 in c. 78.5 in d. 376.8 in

41. QuestionsWolf

31.4 is the circumference of the circle.

42. QuestionsWolf

Hello?

43. QuestionsWolf

Would I multiply that by 12?

44. SeanAcedia

The circumference is 31.4 which is the same lateral surface of the rectangle so you already got your answer.

45. SeanAcedia

the same as the *

46. QuestionsWolf

Okay, thanks. Can you help me with one more?

47. SeanAcedia

sure

48. QuestionsWolf

Canned fruits, vegetables, and soups have labels on the curved surface of the metal container. What is the surface area of the label on this can? That is, what is the can's lateral area? a. 88 cm^2 b. 401.92 cm^2 c. 552.64 cm^2 d. 954.64 cm^2

49. QuestionsWolf

Oh is it 552.64^2?

50. SeanAcedia

You would find the circumference of the circle and you would multiply it by 11. the

51. QuestionsWolf

The circumfrence is, 50.24

52. QuestionsWolf

Multiplied by 11 is, 552.64

53. SeanAcedia

ya you go the right answer

54. QuestionsWolf

Thank-you. You made it so much clearer. :)

55. SeanAcedia

no problem

56. QuestionsWolf

I think that is all, should I close this?

57. SeanAcedia

well if i you have no more questions needed answered i suppose :P gl with your maths