The unit price for sninach is 3.2 cents per ounce at that price how much would 1 pound of spanach cost ( round off the answer to the nearest cent

Ok so...

1 ounce is 3.2

There are 16 ounces in 1 pound

3.2 * 16

51.2

so the spinach would cost 51 cents  

step-by-step explanation:

points a and b are equidistant from the desired line, so the line you find by using them will go through point r.

using points other than a and b will give the desired line only if they are equidistant from r. if they are randomly located, the perpendicular line you create will not necessarily go through point r, hence will not be a solution to the problem.