The sum of eighteen and the product of one and a number x ?

The lines shown below are parallel. if the green line has a slope of -1, what is the slope of the red line

Thelime contains the point(-3,0) and parallel x-3y=3( show all work)

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).