## anonymous one year ago composite figures

1. anonymous

2. anonymous

This is pretty much one long cylinder. r is given as 3 and h is 24 because there are 3 cylinders joined together.

3. anonymous

i got 100.48

4. anonymous

?

5. anonymous

6. anonymous

can you show me what you did?

7. anonymous

2(pi)r^2 = 2(3.14)*(2)*(2)

8. anonymous

=25.12

9. anonymous

r = 3 in the picture

10. anonymous

2(pi)rh = 2(3.14)*(2)*(6) = 75.36

11. anonymous

oh opps thats the wrong one

12. anonymous

13. anonymous

this one.. i am looking at

14. anonymous

ok. so then you need to use 18 for h because you have three 6" cylinders back to back

15. anonymous

ok

16. anonymous

let me change it

17. anonymous

228.08?

18. anonymous

i mean 226.08

19. anonymous

yes and then add the 25.12 you got for the circles

20. anonymous

226.08+25.12 = 251.2

21. anonymous

yes. that's it

22. anonymous

yaay thanks

23. anonymous

you're welcome

24. anonymous

ur smart

25. anonymous

lol thanks

26. anonymous

ok can u help me with the other one

27. anonymous

since ur the genius here

28. anonymous

ok

29. anonymous

30. anonymous

First find the area of the prism

31. anonymous

the square?

32. anonymous

yes the box. Do you need help with that part? |dw:1435191242466:dw|

33. anonymous

A=l*w ?

34. anonymous

176

35. anonymous

right. and you need to do that for each side of the box. |dw:1435191340603:dw|

36. anonymous

So the top, bottom, front, and back are 176 The left and right are 121. And you add them all up to get the surface area of all six sides Does that make sense?

37. anonymous

ok yea it does

38. anonymous

what did you get for that part?

39. anonymous

770

40. anonymous

?

41. anonymous

no wait

42. anonymous

946?

43. anonymous

4 sides with are 176 and 2 side with area 121 SA = 4*176 + 2* 121

44. anonymous

4*176=704

45. anonymous

2*121=242

46. anonymous

so 2(pi)^2 =2(3.14)*(4)*(4) =100.48

47. anonymous

2(pi)rh = 2(3.14)*4*9 =226.08

48. anonymous

leave this part out. so 2(pi)^2 =2(3.14)*(4)*(4) =100.48

49. anonymous

ok

50. anonymous

that section is already included in the rectangle. Using it results in double counting

51. anonymous

huh? ok u confused me

52. anonymous

|dw:1435192776377:dw|

53. anonymous

so A = 704+242+226.08

54. anonymous

yes i got that

55. anonymous

56. anonymous

do i add 226.08 + 100.48?

57. anonymous

no just leave the 100.48 out completely

58. anonymous

226.08 is wrong how??

59. anonymous

Did you add the 704 and 242? |dw:1435193990696:dw|

60. anonymous

ohh

61. anonymous

A = 704+242+226.08 = 1051.08

62. anonymous

okok