Question

A triangle, RST, is reflected across the y-axis to form the triangle \( R'S'T' \) in the standard \( (x, y) \) coordinate plane; thus, \( R \) reflects to \( R' \). The coordinates of point T are \( (j, k) \). What are the coordinates of point \( T' \)?

• A. \( (-j, k) \)
• B. \( (j, -k) \)
• C. \( (-j, -k) \)
• D. \( (k, j) \)
• E. It cannot be determined.

Hint:

When reflecting points across the y-axis, negate the x-coordinate while the y-coordinate remains unchanged.

Answer 1

The Correct Option is C

When a point \( (x, y) \) is reflected across the y-axis, the new coordinates become \( (-x, y) \). Thus, reflecting point \( T(j, k) \) across the y-axis gives the new point \( T'(-j, k) \).
Final Answer: \[ \boxed{(-j, -k)} \]