Atruck has a full 50-gallon gas tank. it uses 7 gallons on the first part of its journey, 13 gallons on the second part of its journey, and 15 gallons on the third part of its journey. how many gallons of gas remain in the gas tank?

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.

step-by-step explanation:

where is the question is there is a formula or is there not one