Given the function:

Let's evaluate the function for x = -8 and x = 5.
• For x = -8
Using the piecewise function, when x is less than 0, we have:
f(x) = 2x
Thus, for x = -8, substitute -8 for x and evaluate.
f(-8) = 2(-8) = -16
f(-8) = -16
• For x = 5
Using the piecewise function, when x is greater than or equal to 0, we have:
f(x) = 0
Thus, we have:
f(5) = 0
ANSWER:
• For x = -8; f(x) = -16
• For x = 5; f(x) = 0