The line y = x is transformed to create the line y=−12x−1. which of the following may be used to describe the transformation? select all that apply.

a. all x-values are opposites of half the original x-values.

b. the graph is reflected across the y-axis, moved 1 unit down, and the rate of change is halved.

c. all x-values are half the original x-values.

d. the graph is reflected across the y-axis, moved 1 unit down, and the rate of change is doubled.