Question

I really need help. Find the volume of a box that has a regular pentagonal base with sides measuring 7.3 inches and height measuring 15 inches. Round 2 decimal places.

Answer 1

@nikato

Answer 2

@TQKMB

Answer 3

Try putting the info in a volume calculator just put in the sides and the height and it will give you the volume.

http://easycalculation.com/area/prism.php

Answer 4

Did you guys do trigonometry in your geo class last year?

Answer 5

Maybe??

Answer 6

how do i figure out the apothem length?

Answer 7

@TQKMB

Answer 8

Is this a pentagonal prism or pyramid?

Answer 9

if its a box i think its a prism hopefully

Answer 10

my teacher did something like this but i didnt understand a thing

Answer 11

sorry it's 1/2 base x length x height

Answer 12

ok but i still dont know how to do it myself

Answer 13

do you know how to multiply?

Answer 14

yeah im a 10th grader ...........would it be 1/2*7.3*15?

Answer 15

you need three measurements
1/2 is a constant

Answer 16

that is where i get stuck , how do i know how much is the base? and i dont know how to do the trigonometry in this problem either

Answer 17

remember, you were taught this a few days ago on one of your post by @celestialdictator?

Answer 18

can you do the rest now?

Answer 19

is this what your teacher trying to show you?
I can't see what you wrote in that notebook of yours

Answer 20

there is also a formula for this very specific type of pentagonal prism
you can try to memorize it, but the approach I provided you is the systematic way of showing how to approach the problem

Answer 21

sorry i took long to answer, im trying to do it now

Answer 22

my teacher did something like this: \[\tan54=\frac{ h }{3.65 }=5*\frac{ 1 }{2 }*7.3(3.65*\tan54) 15 \] and then \[3.65\tan54=h\] and i was so confused

Answer 23

for cos54= adj/7.3 i got 4.29 and for sin54=opp/7.3 i got 5.91