Question

WILL GIVE METAL FOR THE BEST ANSWER
Simplify: square root of 3 times square root of 21
square root of 24

square root of 63

3 square root of 7

Answer 1

\[\sqrt{3}\sqrt{21} = \sqrt{3}\sqrt{3*7}=\sqrt{3}\sqrt{3}\sqrt{7}=3\sqrt{7}\]

Answer 2

It is the second chouice!

Answer 3

choice** @Torri_

Answer 4

Thank you so much @Tom_Boy_Rebel enjoy your metal!

Answer 5

Last choice

Answer 6

second choice isn't simplified...

Answer 7

Thank you @Torri_ Have a nice day!

Answer 8

sorry @Tom_Boy_Rebel ... @mtbender74 said that the last choice was the right answer and i agree, i will have to take back the metal and give it to @mtbender74

Answer 9

thanks @Torri_

Answer 10

No its fine @Torri_ :D but that means that I need help so can you please explain @mtbender74

Answer 11

Certainly...

What you did was right...
\[\sqrt{3}\sqrt{21} = \sqrt{63}\]
But to simplify, you need to factor the number and see if you have a pair that can pull out..
\[\sqrt{63}=\sqrt{3*3*7}\]
Since you have a pair of 3's, they can come outside of the radical as a single 3...leaving you with

\[3\sqrt{7}\]

What i did is the same, i just factored the 21 first and then combined the two root 3's...