Question

Simplify 4*sq rt of 8 x 5*sq rt of 3

a. 240* sq rt of 2
b. 80* sq rt of 6
c. 120* sq rt of 2
d. 40* sq rt of 6

Answer 1

B ?

Answer 2

\[4\sqrt 8 \times 5\sqrt3\]\[=(4\times5)\times\sqrt{8\times3}\]\[=\cdots\]

Answer 3

97.97958971132712

Answer 4

dont approximate the irrational component

Answer 5

Don't calculate any decimals, just multiply the 4x5 then the 8x3. That gives you \[20\sqrt{24}\], right? How could you simplify the square root of 24 even more to get one of the answers you listed? There are several ways to split it up -- \[\sqrt{24}=\sqrt{2}*\sqrt{12}=\sqrt{3}*\sqrt{8}=\sqrt{4}*\sqrt{6}\] , etc. Which way of splitting it up is the best that can be simplified to give you one of the answers you can choose from?

Answer 6

\[\huge \color{green} {4\sqrt{8} \times 5\sqrt{3} = 20\sqrt{8 \times 3} = 20 \times 2\sqrt{2 \times 3}}\]

Answer 7

i dont understand

Answer 8

What don't you understand, how to split up the square root of 24 into two square roots like 2 and 12, or 3 and 8, or 4 and 6?

Answer 9

Or do you not understand what to do after that?

Answer 10

all of it. i end up getting weird answers when i try solving them

Answer 11

Well, show your steps so we can see where you get hung up. Starting from the beginning, how do you start to simplify?

Answer 12

UnkleRhaukus already did step one for you. What next?

Answer 13

i aldrady gave him the answer i came up with

Answer 14

Don't calculate out any decimals, just keep simplifying. The answers you can choose from all don't involve any decimals, so don't do that. Look at what I said before, about how you can split the square root of 24 up. 24 comes from doing 1 * 24, or 2 *12, or 3*8, or 4*6. Let's try splitting up the 24 into the 4 and 6: \[20\sqrt{24}=20\sqrt{4*6}=20\sqrt{4}\sqrt{6}\]
Okay so far?

Answer 15

we cant tell whats wrong from just an answer, we need to make sure you did it in a logical way

Answer 16

so i solve this problem by doing the square root of 4 times t he square root of 6 times 20 ? @mbradar2

Answer 17

correct

Answer 18

and i got the same answer as before 97.97958971132712. how does that help me solve this ? ughhh !

Answer 19

Again, don't calculate out any decimals, your final answer will have square roots. So we have \[20*\sqrt{4}*\sqrt{6}\] so far, right? What is the square root of 4 equal to?

Answer 20

The answer is just a step or two away.