Answer:
f(4) = 124
Step-by-step explanation:
To find f(4), substitute 4 into x and simplify.
[tex]f(x)=x^4 - 2x^3 +5x^2 -20x -4\\f(4) = 4^4-2*4^3+5*4^2-20*4-4\\f(4) = 256 -2*64 + 5*16 -80-4\\f(4) = 256 -128+80-80-4\\f(4) = 128+80-80-4\\f(4) = 208 -80 -4\\f(4) = 128 - 4\\f(4) = 124[/tex]