1. Solving Equations by Graphing - Y2=0 Method Move all terms to the left hand side of the equation, so that zero is on the right hand side. Example Solve the equation: Let Y1 = left hand side of the equation. Let Y2 = 0 You can think of this as being the right hand side of the equation.

2. Slide 2 Find a suitable graph window that shows where the graph intersects the x-axis. In this case ZOOM|ZStandard is sufficient. Example Solve the equation: Solving Equations by Graphing - Y2=0 Method We now want to find the x-intercepts. These are the points (x,0) where, for a given value of x, the y-value is zero, or Y1 = 0.  

3. Slide 3 Example Solve the equation: Recall that Y2=0 is a horizontal line, which is actually the x-axis … Since the line is the x-axis, it is “hidden”, and its not obvious looking at the calculator screen that we have actually drawn two curves on the graph. Solving Equations by Graphing - Y2=0 Method

4. Slide 4 Example Solve the equation: Use CALC|intersect (explained in an earlier module) to find the intersection points of the curve and the line. Note that these points are also the x-intercepts of the curve The point on the left is approximately (- 0.24, 0). The point on the right is approximately (4.24, 0) Solving Equations by Graphing - Y2=0 Method

5. Approximate solutions to the equation are x = - 0.24, 4.24. Slide 5 To confirm that these are correct solutions, use TABLE. TBLSET, Ask TABLE Enter the two x-values in the x-column and notice that the values in the Y1 column are approximately zero, as they should be. Solving Equations by Graphing - Y2=0 Method

6. Slide 6 Solving Equations by Graphing - Y2=0 Method The solutions just found were to the equation Example Solve the equation: Note that these are the same x-values that satisfy the original equation

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