Question

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

Answer 1

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.

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

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

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

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

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

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

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

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I hope that this was helpful.