## Elementary Geometry for College Students (7th Edition)

(a) The point $(4,-3)$ lies on the graph. (b) The point $(8,1)$ does not lie on the graph.
(a) We can verify if the point $(4,-3)$ satisfies the equation of the graph: $5x-4y = 5(4)-4(-3) = 20+12 = 32$ The point $(4,-3)$ lies on the graph. (b) We can verify if the point $(8,1)$ satisfies the equation of the graph: $5x-4y = 5(8)-4(1) = 40-4 = 36$ The point $(8,1)$ does not lie on the graph.