Data Sufficiency

Brent@GMATPrepNow wrote:

gmattesttaker2 wrote:Hello,

Can you please assist with this?

What is the degree measure of angle X?

(1) Angle Y measures 45 degrees.
(2) Line segment AB = √2

OA: A

I was thinking that because Y and X are opposite angles, X = 45 but I am not positive if this reasoning is correct. Thanks for your help - Sri

Hey Sri,

Your rationale is perfect.
Since x and y are opposite angles, they must be equal. So, since statement 1 tells us angle y = 45º, we can be certain that angle x = 45º as well.

Cheers,
Brent

[email protected] wrote:Hi Sri,

Brent has confirmed your logic for Fact 1, but I'm not sure if you had any questions about Fact 2.

For Fact 2, we're given the hypotenuse of the right triangle. In a right triangle, if we only have the value of one side and neither of the other two angles, then there's no way to deduce the value of the two missing sides nor the two missing angles.

Here, we're told that the hypotenuse is root2. The two missing sides COULD both = 1 (so we'd have a 45/45/90 triangle), BUT it's possible that the two missing sides are other numbers (so we'd have two different angles). So Fact 2 is INSUFFICIENT.

GMAT assassins aren't born, they're made,
Rich