Step 1: Turn off the STAT PLOT; press 2nd, Y =, ENTER, right arrow, ENTER. Step 2: Clear the functions: press Y = then, CLEAR for each function that needs deleting. Step 3: Select values for the viewing window; press WINDOW. Use the keypad to type the values. Use up and down arrow keys to scroll through the list. Xmin, Xmax, Ymin, and Ymax identify how much of the x and y-axis will appear in your viewing window. Xscl and Yscl represent the scale of the graph. Step 4: Input the given equation; press Y =. Use the keypad to type the equation. Step 5: Graph the function; press GRAPH. Step 6: Go to the CALCULATE menu; press 2nd, TRACE. Step 7: Go to the zero feature; press 2, use the left arrow to move the cursor to the left of the x-intercept; then, ENTER, use the right arrow to move the cursor to the right of the x-intercept; then, ENTER, ENTER. The x-intercept of the function y = 2x + 3 is -1.5. |
Quadratic and cubic functions may have more than one x-intercept. In this case, you must find the x-intercepts one at a time. Use the steps shown in Example 3 for each x-intercept.