Pearson Algebra 2 Common Core, 2011
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Pearson Algebra 2 Common Core, 2011 View details
5. Quadratic Equations
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Exercise 28 Page 229

Push Y= and type the equation in the first row.

x≈ - 0.59 and x≈ 2.26

Practice makes perfect
The given equation is already in standard form. 3x^2-5x-4=0 We can enter it in the calculator by pushing Y= and writing the non-zero side in the first row.
Window with inequality

Next, by pushing GRAPH, the calculator will draw the graph of the equation. Note that we are looking for x-values that make the y-value equal 0.

Window with a graph

We are able to see that the graph intersects the x-axis twice and there are two zeros. To find them, we can use the zero option in the calculator. This can be found by pressing 2ND and then CALC.

Graffönster från TI-82

After selecting the "zero" option, we need to choose left and right boundaries for one of the zeros. Finally, the calculator asks for a guess where the zero might be. After that, it will calculate the exact point for us. We will have to do this twice, once for each zero.

Window with a graph
Window with a graph

This equation's solutions are x≈ - 0.59 and x≈ 2.26.