Hey wahooza,

Interesting question. Let me tackle the second one first. If they ask:

What is x - y?

There is a pretty significant chance that you WON'T be able to solve for each independently, but you WILL be able to find that difference. They're asking you for that difference for a reason - namely, to eliminate the test-takers who don't see that you could theoretically solve for x - y while not knowing either value specifically.

In this case, you should really start thinking about ways that you might be able to find (x - y), such as the Difference of Squares rule (x + y)(x - y) = x^2 - y^2.


In the first case, I don't know that there's any real reason for them to ask that in that way...I'm not saying they wouldn't but I struggle to find why they would since you're right that you're really just determining if you can solve for x. I suppose they could embed 6x in a parenthetical or fractional term and see if you could solve for just the 6x quicker...

So you're right about the first case, but I doubt that it gives you a whole ton of strategic value. What's more important is really understanding that second case:

If they ask you "what is the value of ________" and the ______ is an algebraic term, they probably asked for that specific term for a reason so you should start thinking of how you can find that. Pay very close attention to the subtlety of wording in these questions/statements as the authors are pretty careful with the way they write them.