How to solve a quadratic equation on a GDC (graphical display calculator). This explanation uses the TI-82/83/84 calculators.1. Press Y= to select the equation entry menu.
2. Enter your quadratic equation followed by ENTER.
3. You could press press GRAPH but it is better to press ZOOM then press 6 or select ZStandard.
4. You will see a display of your graph. Press ZOOM again then press 1 or select ZBox
5. Once back on the graph display, use the cursor keys and press ENTER at the top left and bottom right to create a zoom box
By repeated zooming in and use of the TRACE function you can obtain an accurate estimate of where the curve crosses the x-axis.
Software/Applets used on this page
Glossary
equation
A statement that two mathematical expressions are equal.
function
A rule that connects one value in one set with one and only one value in another set.
gdc
graphic display calculator
graph
A diagram showing a relationship between two variables.
The diagram shows a vertical y axis and a horizontal x axis.
The diagram shows a vertical y axis and a horizontal x axis.
quadratic
A mathematical expression of the 2nd degree; having a x² term but no higher one.
solve
To find the answer or solution to a problem.
union
The union of two sets A and B is the set containing all the elements of A and B.