What effect the transformation has had on the entropy

Question

Response to the following problem:

The outputs x₁, x₂, and x₃ of a DMS with corresponding probabilities p₁ = 0.45, p₂ = 0.35, and p₃ = 0.20 are transformed by the linear transformation Y = a X + b, where a and b are constants. Determine the entropy H(Y ) and comment on what effect the transformation has had on the entropy of X.

Make sure you use enough details to support your answer.