Question

Find a volume for the regular pyramid
https://media.glynlyon.com/g_geo_2012/8/groupi77.gif

Answer 1

so do you know what is formula for volum of a pyramid ?

Answer 2

\[ height * length * width * \frac{1}{3}\] plug in all the given information :)

Answer 3

ok


but can you explain why us this formula ?

Answer 4

so and how you get height of pyramid ?

Answer 5

please explain this step by step, i am learning this online with terrible explanations

Answer 6

so if you see this pyramid there are 3 conguent triangle by side and on the base again one triangle what is congruent with these 3


these triangles are congruent sides


what is the name of this triangles ,so if there are equale sides what mean this again by angles ?

Answer 7

do you understand me ?

Answer 8

3 equale sides result 3 equale angles so how name you this triangle ?

isoscelle ?

Answer 9

no ,because isoscelle mean just two equale sides and there are 3 equale sides

so this mean that these triangles are equilaterale

Answer 10

do you know how many degree has an angle of an equilateral triangle ?

Answer 11

equilateral

Answer 12

yes

Answer 13

30 60 90

Answer 14

why ? above i have wrote that this triangle has 3 equale sides what mean that has 3 congruent angles


right ?

Answer 15

right one moment

Answer 16

60 60 60

Answer 17

yes

Answer 18

do you know formula of volum for a pyramid ?

Answer 19

v=1/3*ba*h

Answer 20

what mean ba ? and what mean h ?

Answer 21

base area and height

Answer 22

height of what ,of a side ?

Answer 23

I don't know that's what the page told me, the volume is one third of the area of the base times the height

Answer 24

just show me your way of the formula

Answer 25

no i will like to learn you exactly how you can solving the same problem

ok ?


so this height mean the height of pyramid ,what you need to calculi it because you dont know it

Answer 26

but you need to calculi first of all area of base


how ?

Answer 27

30

Answer 28

area of base = base time altitude divide 2

Answer 29

so how you have got 30 ?

Answer 30

no sorry thats BF

Answer 31

BF = 2

Answer 32

how can i find AF?

Answer 33

BF = 4/2 =2

Answer 34

do you know what mean sinus of an angle ?

Answer 35

no please explain

Answer 36

so sinus of an angle is equale opposite side divide hypothenuse

Answer 37

so you need using this for you can calculi this altitude of base


ok ? than how ?

Answer 38

it's something divided by 4 in this case, so is it 60/4?

Answer 39

what is this 60 ?

Answer 40

or you wann saying that sin 60 = AF / 4

yes ?

Answer 41

so what mean sinus of angle C or angle B is equal opposite side what is AF divide by hypothenuse what has lenght of 4

Answer 42

since AF is the height, how can i divide it by the hypotenuse if i don't know its value?

Answer 43

the value of AF

Answer 44

not needed just hence you write the sinus of angle C or B

Answer 45

so and now using this and hope you know the numericaly value of sinus 60 degree what is sqaroot3 divide 2


so using this and what you know again the lenght of hypothenuse so from these you can calculi easy the lenght of AF


yes ?

Answer 46

do you understand it ?

Answer 47

ok, but it would be better if you could write it out please because i'm more visual

Answer 48

sorry but i need to go and this is a big complex exercise so because after this you need to calculi again the height of pyramid

Answer 49

so for AF


sinC = AF/AC

sin60 = AF /4

sqrt3 AF
---- = ----
2 4

cross multiplie


4sqrt3 = 2AF divide both sides by 2


2sqrt3 = AE


ok ?

Answer 50

alright i appreciate your time anyway and i apologize for my lack of knowledge in this

Answer 51

ok


so using this you can calculi easy area of base


yes ?

Answer 52

so was my pleasure


yw


good luck


bye

Answer 53

goodbye thankyou