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ariadna.peretz
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If P= x^a+b/x^b what is p?

by ariadna.peretz Fri Aug 31, 2012 1:52 am

Algebra strategy guide, 5th edition. Chapter 8, question 8:

If P= x^a+b/x^b what is value of positive integer p?
a. x=5
2. a=0

The Answer is B but it goes on to say that Statement 1 is Sufficient and Statement 2 is Insufficient. Maybe that's an error?

Anyhow, I was able to simplify the equation to x^a but then I was stumped. Can you tell me how to move forward on this question?

Thanks so much,

Ariadna
RonPurewal
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Re: If P= x^a+b/x^b what is p?

by RonPurewal Wed Sep 05, 2012 3:35 am

you simplified the expression to give x^a. that's 90% of the problem, right there.

statement 1:
now you're looking for the value of 5^a. that can have lots and lots and lots of different values.
not sufficient.

statement 2:
now you're looking for the value of x^0. if x is a positive integer, x^0 is always 1.
sufficient.

if the words "not sufficient" and "sufficient" are indeed reversed in the answer key, please go to this link, select "Errata", and submit your correction:
http://www.manhattangmat.com/contact_form.cfm
thanks in advance.