Understanding different slopes

Question

On my Math praxis, there is always a graph that has a line with two arrows at the ends. One arrow may be labeled "A" and the other "B". They always ask if A is increasing as B is decreasing or vice versa. My question is, how do you know if one is increasing or decreasing? I would give a picture on here, but I don't think that's possible. For example, I had one recently and on the graph the lines formed a "U" shape on the upper half of it. HOW do you figure out the relationship between the two?!

Answer 1

If a line goes up reading from left to right the line is "increasing."

If a line goes down reading from left to right the line is "decreasing."

 

I assume the ∪ shaped graph is a parabola. On the left side the graph is decreasing. After the lowest point, the graph is increasing.