Question

If `f(x)=7x^2-4x`, what is the value of `f(2)`?

Answer 1

`f(2)=20`

Explanation:

`"To evaluate "f(2)" substitute x = 2 into "f(x)`

`f(color(red)(2))=(7xxcolor(red)(2)^2)-(4xxcolor(red)(2))`

`color(white)(xxx)=28-8=20`