To determine which ordered pairs lie on the graph substitute the x- coordinate of the point into the right side of the equation and compare the value obtained with the y- coordinate
(- 20, - 49 )
2x + 9 = (2 × - 20) + 9 = - 40 + 9 = - 31 ≠ - 49
(1, 10 )
2x + 9 = (2 × 1) + 9 = 2 + 9 = 11 ≠ 10
(0, 9 )
2x + 9 = (2 × 0) + 9 = 0 + 9 = 9 ← point lies on graph