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by Scott@TargetTestPrep » Thu Jan 18, 2018 1:42 pm
Vincen wrote:Does x = y?

(1) 4x - 2y = 80
(2) x = (40 + y)/2
We need to determine whether x = y.

Statement One Alone:

4x - 2y = 80

Simplifying the equation we have, 2x - y = 40; however, we cannot determine whether x = y. If we let x = 0 and y = -40, then we see that x is not equal to y. However, if we let x = 40/3 and y = 40/3, then x = y.

Statement Two Alone:

x = (40 + y)/2

Simplifying the equation, we have:

2x = 40 + y

2x - y = 40

Again, we cannot determine whether x = y.

Statements One and Two Together:

Using both statements together, we see that they produce the identical equations of 2x - y = 40; thus, we cannot determine whether x = y.