Geometry

Question Analysis:
Tests understanding of vertical line reflections, contrasting with horizontal lines.

Key Concept Explanation:
Vertical lines (x = constant) are parallel to y-axis
Reflection rule: x = c → x = -c
The line "flips" to the opposite side of the y-axis

Step-by-Step Solution:
Original equation: x = -3
Apply reflection: x-coordinate sign changes
New equation: x = 3

Option Analysis:
A) Correct - proper sign change
B) Incorrect - changed to horizontal
C) Incorrect - no change
D) Incorrect - wrong orientation and value

Common Mistakes:
Keeping the equation unchanged
Changing to horizontal line