Question

An illustration of a coordinate plane with four quadrants shows the x-axis extending from -9 to 9 in increments of 1 and the y-axis extending from negative 11 to 11 in increments of 1. A triangle A B C is plotted on the graph. The triangle A B C has its vertices marked with closed points at A (2, -1), B (6, -3), and C (1, -3).
Reflect triangle ABC with respect to the x-axis and the y-axis. What are the vertices of triangle A′B′C′?
A. The vertices of triangle A′B′C′ are A′(−2, 1), B′(−1, 3), C'(−6, 3).
B. The vertices of triangle A′B′C′ are A′(−2, 1), B′(−6, 3), C'(−1, 3).
C. The vertices of triangle A′B′C′ are A′(2, 1), B′(6, 3), C'(1, 3).
D. The vertices of triangle A′B′C′ are A′(−2, -1), B′(−6, -3), C'(−1, 3).

Answer 1

Reflecting across the x-axis then the y-axis (or across both) sends (x,y) to (-x,-y). Apply to each vertex:

- A(2, -1) → A′(-2, 1)
- B(6, -3) → B′(-6, 3)
- C(1, -3) → C′(-1, 3)

So the correct choice is B.