Question

need help with surface area of pyramids for my friend @Rachel411. Please explain :)

Answer 1

@hartnn

Answer 2

@nincompoop

Answer 3

u know the formulas ?

Answer 4

They told us we could use the theorem but would teach that next week, and yes, hartnm, I do know the pyramid lateral and total surface area formulas.May I tell you what I got on this ome?

Answer 5

yes.

Answer 6

To start with:
Figure : Pyramid
P (Perimeter of square) ...
B ( Area of base ) ...

Answer 7

Ok. figure sq piramyd
p 28 cm
b 49 cm
lateral 336
total 114

Answer 8

Did I do that correctly?

Answer 9

how could your lateral be more than your total?

Answer 10

Let me retry.

Answer 11

in your cylinder questions also, all your total surface area were less than lateral.... i think you forget to add lateral surface area to base are to get total surface area

Answer 12

oops meant 24 for p

Answer 13

oh.

Answer 14

28 was right lol

Answer 15

Total surface area must be greater than lateral surface area.

Answer 16

really.o okay.

Answer 17

P = perimeter of base = 4*7=28
that was correct

Answer 18

Yes,that is what I did.

Answer 19

7*7 is 49.

Answer 20

what formula for lateral u used ?

Answer 21

1/2 pl

Answer 22

oh 112

Answer 23

For lateral?

Answer 24

formula is correct

Answer 25

I think that was because I used web2.0calc.

Answer 26

lateral =112 is correct

Answer 27

i told you to use a different calculator lol

Answer 28

what formula for total ?

Answer 29

Thank you, Hartnn. Ari, will you please snapshot all problems and upload them here? I shall then bookmark them and post them as I finish the problems,with my answers written/typed on thelines.

Answer 30

yup lol
srry

Answer 31

ph+2b

Answer 32

i've already send hartnn the link to the others :)

but here ya go again. https://docs.google.com/file/d/0BwF7ycixAkNZV2NGdWt2UjR3M0k/edit?pli=1

i gotta do chemistry, i'll see you later, ok?

Answer 33

sent*

Answer 34

Thanks:)
so you took all the snapshots?

Answer 35

hey, easier formula for total surface area will be to add B(base area ) to lateral area

Answer 36

no, i just used the googledocs thing

Answer 37

Okay. thank you ari and hartnn.

Answer 38

I will try them now. I do not want to take up your time.

Answer 39

ps i got 114 for totAl

Answer 40

lateral = 112 and total = 114 ?? how is that possible ?
show your work.

Answer 41

okay.
brb

Answer 42

is h 8?

Answer 43

slant height = 8
and denoted by l
what is your h ?

Answer 44

is it 7?
i am not sure what the normal height is.

Answer 45

normal height is not required...
but if u want to find, u use pythagoras theorem

Answer 46

lh..since the formula for total surfsce is Ph+2B

Answer 47

oooh

Answer 48

Dumb me, i was looking at the formula for prisms

Answer 49

hey, easier formula for total surface area will be to add B(base area ) to lateral area

Answer 50

so sorry

Answer 51

mk, let me work it out again

Answer 52

161?

Answer 53

is it same
e for triangular prisms?

Answer 54

yes, 161 is correct :)

Answer 55

yay i get it now:)
wt about triang prisms

Answer 56

Is it the same for triangular prisms?

Answer 57

same what ? formulas ? no

Answer 58

How are they different?

Answer 59

area of base is not the square of its side....

Answer 60

is your triangular prism regular ?

Answer 61

um a triangular prism is number two. refer to google docs link,please.

Answer 62

oh, yeah..... the base is equilateral triangle.... u know the formula for area of equilateral triangle ?

Answer 63

umm, side a + side b+ side c?

Answer 64

that would be perimeter of base = 3* side = ?

Answer 65

I am not sure, we were not told.

Answer 66

Will you explain?

Answer 67

perimeter of base = 3* side = 3*10 = ?
perimeter of base means sum of sides of base, here the base sides are all 10, so sum = 3*10 = ?

Answer 68

30

Answer 69

i got area of base to be100?

Answer 70

what formula for area of base you used ?

Answer 71

i did it right???? mouth drops open

Answer 72

sorry, P =30

Answer 73

i used a = bh
so 10 x 14

Answer 74

yes i wrote that earlier.
i got b as 100?

Answer 75

area of equilateral triangle is not bh ....

Answer 76

but is 100 correct?

Answer 77

nopes.

Answer 78

oh. let me try again

Answer 79

it is not 70 either,is it?

Answer 80

area of equilateral triangle = \(\huge \frac{\sqrt3}{4}(side)^2\)

Answer 81

We have not been taught that.

Answer 82

And is the height 14?

Answer 83

then how come they ask questions on this ?

Answer 84

Idk...I didnnot make the worksheet.
Will you tell me what you got?

Answer 85

actually u use pythagoras theorem to find prism height

Answer 86

oh. Okay. I gotta go. I will give it another shot tomorrow.
See you,and thanks, Ari,and Hartnn.

Answer 87

did u go through pyramid questions u seked ?

Answer 88

*asked

Answer 89

Not all of them,but I will try again tomorrow.

Answer 90

ok, bye for now.

Answer 91

Bye.