Question

On a coordinate plane, a triangle has points R (negative 3, 4), T (negative 1, negative 4), and S (negative 4, negative 2). What are the coordinates of the image of vertex R after a reflection across the y-axis? (–4, 3) (4, –3) (–3, –4) (3, 4)

Answer 1

Answer:

(3,4)

Step-by-step explanation:

if the original is (-3,4) and its a reflection over a vertical line that's the y-axis, the x would become opposite, which would mean -3 becoming 3.

Answer 2

Answer:

Reflection across the y-axis and a dilation by a factor of 2.

Step-by-step explanation:

Comparing the points from the pre-image, ABC, to the image, A'B'C', we see that both x- and y-coordinates seem to be doubled from the pre-image to the image. However, the sign of the x-coordinates in the image is different; this means that the x-coordinates are negated.  A reflection across the y-axis will negate the x-coordinates.

To double both the x- and y-coordinates, we would then apply a dilation by a factor of 2, as the scale factor gets multiplied by every coordinate.