## anonymous 5 years ago find the height of a prism of a base if the volume is 9 and the area of the base is 18

1. anonymous

volume of a prism = area of base x height so plug in your 2 values and solve the equation

2. anonymous

i assume that the prism is standing on its end!

3. anonymous

if the base of a right prism is a rhombus with diagonals 10 in and 12 in and the volume of the prism is 60 cu in find the height of the prism please help!

4. anonymous

i really dont understand geometry at alll!

5. anonymous

well we usually talk about the length and cross sectional area of a prism. I prism is a 3 dimensional object with a uniform cross section - a bit like a toblerone bar of chocolate

6. anonymous

ok . could you please explain to me how to solve the problem

7. anonymous

well assume the prism is resting on its base which is a rhombus then its volume = area of the rhombus x the height so 60 = area of rhombus x h so we need to calculate the area of the rhombus

8. anonymous

hold on a bit - to be honest i'm stuck with that bit

9. anonymous

ok so its going to be d1d2 divided by 2 to solve for area

10. anonymous

heck! is that the area of a rhombus - you've got that from a maths book or by other means??

11. anonymous

other means but when i calulate it it comes out to 60 = 60

12. anonymous

i dont remember to be honest

13. anonymous

well d1d2 /2 = 30/2 = 15 so qwe have 60 = 15 x h h = 4 height is 4

14. anonymous

where did u get 15 from?

15. anonymous

where did you get 30 from im lost

16. anonymous

sorry - i must be tired its 12 x 10 divided by 2 giving 60 - either the d1d2 formula is wrong or volume = 60 is wrong. hold on and i'll check my maths stuff

17. anonymous

ok - the volume d1d2/2 is correct so the answer must be h = 1 60 = 60 x h h=1

18. anonymous

is that possible?

19. anonymous

lol - thats wrong because the diagonals are in inches and the volume is in cubic feet right 60 cu feet = 60 x 12^3 cu ins = 103680 cu ins so 103680 = 60 x h h = 12^3 = 1728 ins or 144 ft

20. anonymous

phew - i think thats enough for today my brain is tired

21. anonymous

how did you get to that?

22. anonymous

well the volume is 60 cu ft isn't it

23. anonymous

yes

24. anonymous

i 'm going crazy - i've just checked your earlier post - its 60 cu ins there

25. anonymous

in which case h = 1 inch as i said earlier

26. anonymous

that is possible brit

27. anonymous

lol okay thank you but im not done working your brain 2 more questions if you dont mind

28. anonymous

give me a medal first! lol

29. anonymous

ok so the diagonal of a cube is 7$\sqrt{3}$ find the voulme of the cube

30. anonymous

i assume you mean the diagonal of one side of the cube. by pythagoras (7sqrt3)^2 = 2x^2 (where x = one side of cube) 147 = 2x^2 x = sqrt(147/2) = 8.5732 vlume of cube = (8.5732)^3 = 630.13 correct to 2 dec places

31. anonymous

are u still there