I'm having some algebra trouble could somebody help me?

Question

anonymous · Answer

I have no idea for the second one, but for the first one it's either b or c.

anonymous · Answer

@Nnesha, @Godlovesme

anonymous · Answer

for a1,  multiply by the conjugate of the denominator

anonymous · Answer

Ok, so then it would be b.

anonymous · Answer

not exactly. scroll down 3/4 of this page https://www.mathsisfun.com/algebra/rationalize-denominator.html

anonymous · Answer

Then it would be c. I don't remember going over that in class. Thanks for pointing it out.

anonymous · Answer

then read through that webpage, should give you a review and prepare you for the other questions that are similar to this one

anonymous · Answer

ok, once again, thanks!

anonymous · Answer

for b, it's a bit tricky, I'll bruteforce it and list the first few cube roots

anonymous · Answer

let's see. 
1: 1
8: 2
27: 3
64: 4
125: 5
216: 6

the way to read this is the cube root of the left hand side is the part after the colon.
so: $\sqrt[3]{1}=1\\sqrt[3]{64}=4$

anonymous · Answer

so let's evaluate 144/y
The factors of 144. Answer : 1,2,3,4,6,8,9,12,16,18,24,36,48,72,144,
these numbers should give whole numbers under the radical, but we also want the whole cube root to evaluate to a whole number

anonymous · Answer

so while $\sqrt[3]{\dfrac{144}{72}}=\sqrt[3]{2}$
while the 2 is a whole number, the whole radical isn't necessary a whole number

anonymous · Answer

never mind, I thought of a simpler way to think about this

anonymous · Answer

So b is the answer, because cbrt(144/18=2 and cbrt(144/144=1

anonymous · Answer

correct

anonymous · Answer

Sweet!! Thank you so much! I can actually understand this now.

anonymous · Answer

brava because I have no idea what I just did

anonymous · Answer

I hate that feeling.

anonymous · Answer

there's always the feeling of looking at a test and feeling like you're taking an exam in a different country because you understand NOTHING on the paper :p

anonymous · Answer

I have teachers that put random questions on a test and they don't apply to anything we talked about, plus they are not bonus they are actually apart of the test! What the heck?

anonymous · Answer

that doesn't happen in college. it's almost always my fault haha
good luck with the rest of your homework

anonymous · Answer

Thanks!