Ab passes through the points (1,3) and (3,17). if cd is perpendicular to ab, what is the slope of cd?

First of all, we need the slope of AB, which we can compute as

Now, if a line is perpendicular to a given line, their slopes follow this equation:

So, the slope of CD is -1/7

easy its decreasing

step-by-step explanation:

because its top point is at the to of the graph on the left side (atleast from the veiw i see it) now if that top point wast in the lower part of the graph it would be increasing hope this have a nice day