Answer: Midline equation: y = -7
Step-by-step explanation: This function is a sinusoidal function of the form:
y = a.cos(b(x+c))+d
Midline is a horizontal line where the function oscillates above and below.
In the sinusoidal function d represents its vertical shift. Midline is not influenced by any other value except vertical shift. For that reason,
Midline, for the function: [tex]h(x) = -4cos(5x-9) - 7[/tex] is y=d, i.e., [tex]y=-7[/tex]
