Question

The following ordered pairs came from a function transformation. The original ordered pair is (4,9)
, and the transformation ordered pair is (2,9)
. Which of the following correctly identifies the value of k and describes whether the dilation is a horizontal compression or stretch?(1 point)

k = 0.5; stretch

k = 2; stretch

k = 0.5; compression

k = 2; compression

Answer 1

k = 0.5; compression

Reason: horizontal dilation maps (x,y) to (kx,y). Since 2 = k·4, k = 2/4 = 0.5. Because k < 1 this is a horizontal compression.