please help!! tricky square roots!!

Question

anonymous · Answer

attachment

anonymous · Answer

@dpaInc

anonymous · Answer

you only have two type of roots a fourth root and cube root.  
if you think of it this way let x be the 4th root of 2 and let y be the 3rd root of 2
then the expression can be thought of as
6x - 14y + 5y + 7x
can you simplify this and make the necessary choice?

anonymous · Answer

im not good with breaking down, can you show me how step by step?

anonymous · Answer

can you combine like terms here?

6x - 14y + 5y + 7x

like terms are the ones with the same variables...

anonymous · Answer

13x  and 19y ?

anonymous · Answer

13x is correct
but you should get -9y also

so 
13x - 9y is the simplified form.. now all you have to do is replace the x and the y with what we substituted them with and you'll have your answer.

anonymous · Answer

I'm tied between c and d

anonymous · Answer

can't be any of those..
do you see the 13 and the 9? in our answer and the choices?

anonymous · Answer

sorry, 13 and the -9 ...

anonymous · Answer

no but i thought we had to subtract those, thats why i had the 4 in mind

anonymous · Answer

you cannot combine unlike terms... only like terms you can combine.... 4th root is different from 3rd root.

anonymous · Answer

then it must be A

anonymous · Answer

it's B

anonymous · Answer

why?

precal · Answer

|dw:1337813191615:dw|
just like dplanc stated combine like terms