Question

help please

Answer 1

@jim_thompson5910

Answer 2

what do you have so far?

Answer 3

they give me "_=_√_"

Answer 4

ok, so you know what the answer format is

Answer 5

do you have anything so far in terms of work done?

Answer 6

no

Answer 7

ok, so when it comes to diagonals of solid rectangular prisms, you can use this formula

\[\Large d = \sqrt{L^2 + W^2 + H^2}\]

notice how this is very similar to the 2D version of the diagonal length

Answer 8

what happens when you plug in

L = 8
W = 4
H = 2

??

Answer 9

it would be D = √8^2 + 4^2 + 2^2

Answer 10

yeah with 8^2 + 4^2 + 2^2 all under the root

Answer 11

8^2 + 4^2 + 2^2 simplifies to _____

Answer 12

64+16+4

Answer 13

keep going

Answer 14

it would be 84 as the final result

Answer 15

so we have this now: \[\Large \sqrt{84}\]

Answer 16

you need to simplify that

Answer 17

how would I simplify it?

Answer 18

what perfect squares are factors of 84?

Answer 19

let me check

Answer 20

the closest thing I came to was 9. 9^2 = 81

Answer 21

list out the perfect squares:

1, 4, 9, 16, 25, 36, 49, 64, 81, 100

you stop when you pass 84

Answer 22

so I would stop at 81

Answer 23

list out the factors of 84

1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42, 84

Answer 24

compare the two lists

1, 4, 9, 16, 25, 36, 49, 64, 81, 100
1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42, 84

what numbers are in BOTH lists?

Answer 25

1

Answer 26

what else

Answer 27

oh 4

Answer 28

so 84 = 4*21, which means

\[\Large \sqrt{84} = \sqrt{4*21}\]

\[\Large \sqrt{84} = \sqrt{4}*\sqrt{21}\]

\[\Large \sqrt{84} = 2\sqrt{21}\]

Answer 29

I'm using the rule

\[\Large \sqrt{xy} = \sqrt{x}*\sqrt{y}\]

Answer 30

okay. did you simplify 4?

Answer 31

yes I took the square root of 4 to get 2

Answer 32

okay