Answer:
f(3) = 84
Step-by-step explanation:
To evaluate a function for a specific value of the variable, put the value in the function's expression where the variable is, and do the arithmetic.
__
Sometimes it works well to simplify the expression a bit.
f(x) = 16x^2 -20x = 4x(4x -5)
f(3) = 4(3)(4(3) -5)) = (12)(7)
f(3) = 84
