Question

Check my answers, please! (* is my answer.)

Answer 1

I'm no good in math, so an explanation would be great, if offered.
Also, if anyone happens to go to Connexus and understands this unit, help would be apperciated. Thanks!

Suppose that y varies inversely with x, and y = 6 when x = 8. What is an equation for the inverse variation?

y = x/48
y = 2x
*x = y/2*
y = 48/x

Suppose that y varies inversely with x, and y = 0.2 when x = 2. What is an equation for the inverse variation?

y = 1.8x
*y = 0.4/x*
*x = y/1.8*
y = x/0.4

Does the data in the table represent a direction variation or an inverse variation? Write an equationto model the data.

x|2|4|6|8
y|14|28|42|56

direct variation; y = 1/7x
inverse variation; xy = 7
direct variation; y = 7x
inverse variation; xy = 1/7

Does the data in the table represent a direction variation or an inverse variation? Write an equationto model the data.

x|2|4|8|12
y|4|2|1|2/3

inverse variation; xy = 8
direct variation; y = 8x
inverse variation; y/x = 8
*direct variation; y = 8/x*

Answer 2

"y varies inversely with x" MEANS \(y = \dfrac{k}{x}\).

"y varies directly with x" MEANS \(y = kx\).

Look for these patterns.

Answer 3

Mm, alright, I'll try. Thanks!

Answer 4

So, would the first one be the last answer? (48/x)

Answer 5

That is the ONLY possible answer from the given choices.

Answer 6

With a little arithmetic, \(y = \dfrac{k}{x}\) is the same \(x\cdot y = k\) when k is not zero. So, look for that form, too. It's just a minor variation of Inverse Variation.

Answer 7

Alright. I think I've got that...

The second answer would be, B I believe and the last two, C and D?

Answer 8

Wait, it can't be D, right? Because of the k/x not being direct? Would it be B, then?

Answer 9

The second one has to be B, since, again, that's the only one that is INVERSE variation.