Find the value of r so that the line through (r,5) and (6,r) jas a slope of 5/8

Use set builder notation to represent the following set: { -3, -2, -1, 0}

What is the first step of an indirect proof of a number that is divisible by two

Find the measure of the interior angles of the following regular polygons: a triangle, a quadrilateral, a pentagon, an octagon, a decagon, a 30-gon, a 50-gon, and a 100-gon.