2. What is the x-intercept? The x-coordinate of a point where the graph crosses the x- axis. What is the y-intercept? The y-coordinate of a point where a graph crosses the y-axis. The x-intercept is the value of x when y=o. The y-intercept is the value of y when x=o.

3. Finding intercepts Find the x-intercept and the y-intercept of the graph of the equation 2x + 3y = 6 SOLUTION Find the x-intercept of 2x + 3y = 6 Let y = 0. 2x + 3y = 6 Write original equation. 2x + 3(0) = 6 Substitute 0 for y. 2x = 6 Solve for x. x = 3 The x-intercept is 3. The line crosses the x-axis at the point (3, 0).

4. To find the y-intercept of 2x + 3y = 6, let x = 0. 2x + 3y = 6 Write original equation. 2(0) + 3y = 6 Substitute 0 for x. 3y = 6 Solve for y. y = 2 The y-intercept is 2. The line crosses the y-axis at the point (0, 2).

5. You Try! 2x - y = 4 x-intercept let y = 0 2x - 0 = 4 2x = 4 x = 2 (2,0) y-intercept let x = 0 2(0) - y = 4 - y = 4 y = -4 (0,-4) 3y = -6x + 3 x-intercept let y = 0 3(0) = -6x + 3 0= -6x + 3 6x = 3 or -3 = -6x x = ½ (1/2, 0) y-intercept let x = 0 3y = -6(0) + 3 3y = 3 y = 1 (0,1)

6. Use the graph to find the x-intercept and the y- intercept of the line The x-intercept is -3 or (-3,0) The y-intercept is 3 or (0,3)

7. 1. Decide whether 2 is the x-intercept or the y-intercept of the line y = 2x + 2. Explain your choice. y-intercept; when x = 0, y = 2(0) + 2 = 2 2. How many points are needed to determine a line? Two Points 3. Describe a line that has no x-intercept. A line with y = a for any number except 0. For example, y = 2 4. Describe a line that has no y-intercept. A line with x = a for any number except 0. For example, x = -1 Check for Understanding

8. 1. y = x + 2 -2; 2 2. y - 2x = 3 -3/2; 3 3. 5y = 5x + 15 -3; 3 4. x - y = 1 1; -1 Find the x- and y-intercept of the of the equation