Write the equation of the function whose graph is a horizontal reflection of the graph of each of the following functions:

a. y = (x + 7)^2 + 4

b. y = (−x − 11)^2 − 5

c. y = (−x + 9)^2 − 8

d. y = (x − 10)^2 + 15

e. y = x^2 − 4x + 3

f. y = (−x)^2 + 12(−x) + 36