How do you use a graphing calculator to solve quadratic equations?

1 Answer
Oct 30, 2014

Let us look at the following example.

Solve #2x^2+5x-3=0# for #x#.

(Be sure to move all terms to the left-hand side so that you have zero on the right-hand side.)

Step 1: Go to "Y=" and type in the quadratic function.

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Step 2: Go to "WINDOW" to set an appropriate window size.

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Step 3: Go to "CALC", and choose "zero".

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Step 4: It will say "Left Bound?", so move the cursor to the left of the zero and press "ENTER".

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Step 5: It will say "Right Bound?", so move the cursor to the right of the zero and press "ENTER".

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Step 6: It will say "Guess?", then move the cursor as close to the zero as possible and press "ENTER".

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Step 7: The zero (#X=-3#) is displayed at the bottom of the screen.

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Step 8: Repeat Step 3-7 to find the other zero (#X=0.5#).

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I hope that this was helpful.