Since all points on the x-axis have a y-coordinate of 0, to find x-intercept, let y = 0 and solve for x Since all points on the y-axis have an x-coordinate of 0, to find y-intercept, let x = 0 and solve for y

     

Solution Example Graph y = 2 Writing in slope-intercept form: 0 • x + y = 2. No matter what number we choose for x, we find that y must equal 2. y = 2 Choose any number for x x y (x, y) 2 (0, 2) 4 (4, 2) 4 (4 , 2) y must always be 2

Graph y = 2 When we plot the ordered pairs (0, 2), (4, 2) and (4, 2) and connect the points, we obtain a horizontal line. Any ordered pair of the form (x, 2) is a solution, so the line is parallel to the x-axis with y-intercept (0, 2).

Example Graph y = -5

Example Graph x = 2 Solution We regard the equation x = 2 as x + 0 • y = 2. We make up a table with all 2 in the x-column. x = 2 x must be 2 x y (x, y) 2 4 (2, 4) 1 (2, 1) 4 (2, 4) Any number can be used for y

Graph x = 2 When we plot the ordered pairs (2, 4), (2, 1), and (2, 4) and connect them, we obtain a vertical line. Any ordered pair of the form (2, y) is a solution. The line is parallel to the y-axis with x-intercept (2, 0).

Example Graph x = 6