A constant means that the y value is going to be the same no matter what x value you put it. It also is usually a single number, so that is going to be the one that says y=-7.
A joint variation function is when you're variable is proportional to two variable on the other side. The equation has a constant and two variables, which is v=1/3bh.
Direct variation means when one value increases, the other variable increases also. Usually seen as y=kx but can be seen as y/x=k. An example of this is n/m=1.5.
Inverse variation means that as one variable increases the other decreases. This is vw=-18. This can be rewritten as v=-18/w which means the bigger w get's, the smaller v is going to get.
I don't see an example for a step function which is why I didn't do it.
Does this answer your question? An I'd be happy to help you in the future with any other questions you may have.
Let me know partner.
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