Example 3 in your textbook demonstrates how the graphing calculator can be used to solve exponential equations. This method is used primarily if the terms of an exponential equation cannot be written with a common base. Example 4 explains the steps for solving an exponential equation graphically.

Use your graphing calculator to solve .

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 must be deleted.

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.

Step 4: Input both sides of the equation; press Y=. Use the keypad to type both expressions.

Step 5: Graph the expressions; press GRAPH.

Step 6: Reselect values for the viewing window; press WINDOW.

Step 7: Regraph the expressions; press GRAPH.

Step 8: Go to the CALCULATE menu; press 2nd, TRACE.

Step 9: Find the intersection of Y1 and Y2; press 5, ENTER, ENTER, ENTER.

Because you are solving for x in the equation, the answer is the x-value of the intersection point. The solution to is approximately 2.1066.

Read pages 359-360 Example 4 in your textbook, Principles of Mathematics 12.

Complete the Your Turn questions on page 360 (a) and page 364 (14a), for more practice solving exponential equations graphically.

Click here to verify your answers.

Read page 361 In Summary and pages 366-367 Frequently Asked Questions in your textbook, Principles of Mathematics 12.