Find the coordinates of the vertices of the figure after a reflection of the given axis. Then graph the reflection image.

Given:

The coordinates of the triangle ABC are (3,3), (6,5) and (2,1)

We need to determine the vertices of the triangle A'B'C' after reflection across y - axis.

Reflection across y - axis:

The rule to translate the coordinates across y - axis is given by

Let us substitute the coordinates.

The coordinates of the point A' are

The coordinates of the point B' are

The coordinates of the point C' are

Therefore, the coordinates of the triangle A'B'C' are (-3,3), (-6,5) and (-2,1).

Hence, Option C is the correct answer.