Elementary Geometry for College Students (6th Edition)

$5x+2y=5$
When two lines are parallel in standard form, the left side of the equation is the same. Thus, we solve for the new constant on the right side of the equation: $5x+2y = c \\ 5(-1)+2(5) = c \\ c= 5$ Thus, we find: $5x+2y=5$