Question

Question #53cdd

Answer 1

1) yes
2) no
3) no

Explanation:

Linear means the function goes in a straight line.

So for `y=1/2(x-4)`, as there is only one power of `x`, it just increases steadily with a gradient of 0.5.
graph{1/2x-2 [-5, 10, -5, 5]}

`x^2+4` is a quadratic because it has `x` to the power of 2. Anything with an `x`squared will have 2 values for `x` at each `y` value. It's a curved line, therefore non-linear.
graph{x^2+4 [-5, 5, -.5, 15]}

`sqrt(x)-2` can be written as `x^(1/2) -2`. Now it's more obvious that we have `x` to a power, so it's non-linear.

graph{`(x)^(1/2)-2` [-10, 10, -5.21, 5.21]}