What do you think will be the values of y? Quadratic Graphs y = x2 Note: - X - = + So -22 = -2 X -2 = 4 Use it to find the values of x2 x -2 -1 1 2 x2 y 4 1 1 4 4 1 0 1 4 What do you think will be the values of y?

Quadratic Graphs y = x2 x -2 -1 1 2 x2 4 y 1 2 x2 4 y Now join the points with a smooth curve. y = x2 We need to plot the values (coordinates) of x and y on the grid to draw the graph. What happens if y = x2 + 1 or y = x2 – 1. Let’s Find out.

Quadratic Graphs y = x2 y = x2+1 y = x2 - 1 Note: - X - = + So -22 = -2 X -2 = 4 y = x2 y = x2+1 y = x2 - 1 x -2 -1 1 2 x2 4 y Remember X2 is the same as before. All we need is to add 1 to x2 to find y. x -2 -1 1 2 x2 4 x2+1 y 5 2 1 2 5 Let’s do the same for when y = x2 - 1 5 2 1 2 5 x -2 -1 1 2 x2 4 x2-1 3 y Let’s plot all the three graphs on the grid

Quadratic Graphs y = x2 y = x2+1 y=x2-1 x -2 -1 1 2 x2 4 y x -2 -1 1 2 1 2 x2 4 y y = x2 +1 y = x2 x -2 -1 1 2 x2 4 x2+1 5 y y = x2 - 1 x -2 -1 1 2 x2 4 x2-1 3 y What do you notice curves? What do you notice about where the lines cross the y-axis?