Question

Given your sister's incomplete text,

Answer 1

We automatically know the coordinate point is in quadrant 2 or 3 without knowing the y value because every point with a negative x value lands in those squadrants.

Answer 2

The x-coordinate is negative, and the only option for the y-coordinate is a positive or a negative number. If the y-coordinate is positive, then it is located in quadrant 2. If the y-coordinate is negative, then it is in quadrant 3.