SOLUTION: Simplity (sqrt7)(sqrt14) my answer 9.89494937 Simpilfy 5(sqrt5)-(sqrt20) my answer 6.708203932 is not right. Simplify (sqrt5)(sqrt3) my answer 3.87298346 Determine whether (121)

Question 58689: Simplity (sqrt7)(sqrt14) my answer 9.89494937
Simpilfy 5(sqrt5)-(sqrt20) my answer 6.708203932 is not right.
Simplify (sqrt5)(sqrt3) my answer 3.87298346
Determine whether (121)^1/3 is rational or irrational. This is the 3rd root of 121.
Found 2 solutions by stanbon, venugopalramana:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Simplify (sqrt7)(sqrt14)
=sqrt(7^2*2)
=7sqrt2
----------------
Simpilfy 5(sqrt5)-(sqrt20)
=5sqrt5-sqrt(4*5)
=5sqrt5-2sqrt5
=3sqrt5
---------------
Simplify (sqrt5)(sqrt3)
=sqrt15
--------------
Determine whether (121)^1/3 is rational or irrational. This is the 3rd root of 121.
It is irrational because 121 is not a perfect cube.
Cheers,
Stan H.

Answer by venugopalramana(3286) (Show Source): You can put this solution on YOUR website!
Simplity (sqrt7)(sqrt14)
=sqrt(7)*sqrt(7*2)=sqrt(7)*sqrt(7)sqrt(2)=7*1.414=9.898
my answer 9.89494937..OK
Simpilfy 5(sqrt5)-(sqrt20)
=5SQRT(5)-SQRT(5*4)=5SQRT(5)- 2SQRT(5)= (5-2)SQRT(5)=3SQRT(5)=6.7082
my answer 6.708203932 is not right.IT IS CORRECT..OK
Simplify (sqrt5)(sqrt3)
=SQRT(15)=3.873
my answer 3.87298346...OK..
Determine whether (121)^1/3 is rational or irrational. This is the 3rd root of 121.
IT IS IRRATIONAL

RELATED QUESTIONS
sqrt20/5 - 1/sqrt5 Simplify. Thank... (answered by MathLover1)
I have to simplify this; sqrt20/5-1/sqrt5 I keep coming up with that this cannot be... (answered by rapaljer)
x^2 + y^2 = 8 x - y = 2 My answer is (1 + sqrt5, -1 + sqrt5) and (1 - sqrt5, -1 -... (answered by Alan3354,ikleyn)
Is my answer correct? Find the area of the rectangle L=sqrt3+sqrt5 W=sqrt3+sqrt5... (answered by stanbon)
Multiply and then simplify the radical expression: sqrt7(sqrt7 - sqrt5) (answered by Mathtut)
Please help me with this Simplify. sqrt20/5 - 1/sqrt5... (answered by Nate)
Could some on help me please. Simplify... (answered by checkley75)
Simplify. (6 + sqrt5)(6 - sqrt5) I am coming up with 36, but I don't think that is... (answered by Nate)
sqrt5 (6sqrt2 - sqrt5)... (answered by robertb)