Question

Find f(4) when f(x)=4x^2 - 2 x - 4

Answer 1

52

Explanation:

`f(x)=4x^2-2x-4`

`f(4)=4(4)^2-2(4)-4` (I replaced
`x` with
`(4)` since we are to find
`f(4)`.)

`f(4)=4(16)-2(4)-4` (By the order of operations, we take care of the exponents before whatever else we have here.)

`f(4)=64-8-4` (By the order of operations, we take care of the multiplication as we see if left to right.)

`f(4)=56-4` (By the order of operations, we perform addition/subtraction as we see it left to right.)

`f(4)=52` (This completes the simplification.)

We could have also put this in our calculator as:

4(4)^2 - 2(4) - 4

This would have returned 52.