Originally Posted by

**masters** not knowing what kind of calculator you have, it might be difficult to answer your question.

Using a ti-84+, enter the equation using the **y=** key

$\displaystyle y_1=4x^2-2x-3$

press the **graph **key.

Press **2nd** and then the **trace** key to bring up the **calc** menu.

Choose **2: Zero**

using the left arrow key, move the 'spider' to just above the left x-intercept and press **enter** to mark the **left bound** side of your zero, then move the spider just below the x-intercept and press **enter **to mark the **right bound** side of your zero. Press **enter** once more to reveal the zero (x-intercept).

You should've gotten **-.6513878**

that's rounded off, because the exact answer is irrational. Use the quadratic formula to verify this.

You need to repeat this process for the other zero.

By the way, the **spider** is that blinking asterisk of a thing that is tracing the curve when you use the left or right arrow keys.