What series of transformations from △abc to △def shows that △abc ≌ △def?

a). a reflection across the y-axis followed by a translation of 1 unit right and 2 units up

b). a clockwise rotation of 90º about the origin followed by a translation of 4 units right and 4 units up

c). a reflection across the x-axis followed by a translation of 1 unit right and 1 unit down

d). a reflection across the line y=x followed by a positive rotation of 270º about the center

We start with

If we perform a reflection across the x-axis, we will change the sign of all the y coordinates:

If we perform a translation of 1 unit right, we will increase the x coordinates by 1:

If we perform a translation of 1 unit dpwn, we will decrease the y coordinates by 1, and the coordinates of the vertices will match those of the new triangle:

a. the residual plot for model 1 has a random pattern and is a good fit for the data.

step-by-step explanation: