Triangle DEF is the image of triangle ABC after a sequence of transformations. After you reflect ABC in the y-axis, what must you do? Describe a sequence of transformations that proves the triangles congruent.

Step-by-step explanation:

After reflection about y-axis, A'B'C' must be translated down 6 units to create image DEF.

ABC and DEF are congruent due to the following common properties of reflections and translations.

1. does not change the nature of geometric elements, i.e. maps a line to a line,  a segment to a segment, etc.

2. preserve lenths of segments.

3. preserves angles

By the congruent theorem of SSS, the two triangles are congruent.

the answer is b