# Thread: I am an older adult, trying to preparefor the GRE math.. HELP!!!!

1. ## I am an older adult, trying to preparefor the GRE math.. HELP!!!!

problem:

Quantity A Quantity B

x2 + 1 2x-1

A. Quantity A is greater
B. Quantity b is greater
c. Two quantities are equal
d. Relationship can not be determined, from the information given

2. ## Re: I am an older adult, trying to preparefor the GRE math.. HELP!!!!

Lets set them equal:

$x^2+1=2x-1$
$(x-1)^2=-1$

There are no real values for $x$ that will make that equality true. So, plug in a number (say 0). We find that Quantity A is greater. Since both expressions are continuous, this relationship can only change if at some point the two quantities are equal. Therefore, the answrr is A