Answer:
15) I
16) y
Step-by-step explanation:
15) Quadrants are numbered (using Roman numerals) counterclockwise, starting with upper right. The x-coordinates are positive to the right of the y-axis, and the y-coordinates are positive above the x-axis. The point (7, 5) is in the upper-right quadrant, so is in quadrant I.
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16) Changing the sign of the x-coordinate moves the point from the right side of the y-axis to an equal distance away on the left side, or vice versa. This makes the y-axis the line of reflection. So, we say the points are reflections of each other across the y-axis.
