Question

Question #7b5bc

Answer 1

See explanation.

Explanation:

Given that `D(x)=2x`:

`D(x)` is definitely a function since each input generates exactly one output. So that's true.

`x` is the independent variable since you pick an `x` and it determines `D(x)`.

`D(6)= 2*6=12` so `D(6) ne 3`.

`D(x)` is a direct variation since if we let `D(x)=y` then `y=2x` which is direct variation with constant `k=2`

All of the points in the set `{(5,10), (6,12), (-2,-4)}` definitely fit the rule `y=2x`, so this one is true.