The perfect orange calls for 2/3 parts yellow paint and 1/4 parts red paint.
a) how much yellow paint do you need if you use 1 cup of red paint?
b) how much red paint do you need if you use 1 cup of yellow paint?

the line of

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.

a

step-by-step explanation: