How to Solve a Quadratic Equation With a Casio Calculator

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A quadratic equation is one that can be written out in the form

ax^2 + bx + c = 0

where ​a​, ​b​ and ​c​ are numbers (usually, but not necessarily, whole numbers). Learning to solve quadratics is a mainstay of the algebra curriculum and usually requires a great deal of trial and error. Many of the advanced scientific calculators made by Casio, such as the fx-115ES and the fx-95MS, feature the ability to solve quadratics.

MS models

  1. Check the Equation

  2. Check that the equation to be solved is written out in standard form,

    ax^2 + bx + c = 0

    If not, rewrite the equation as necessary.

  3. Press Mode, then 1

  4. Press the "Mode" button repeatedly until "EQN" appears on the screen. Press "1" to enter the equation calculation mode.

  5. Select the Quadratic Equation

  6. Press the right arrow key followed by "2" to select a quadratic equation.

  7. Input Your Values

  8. Input the values of ​a​, ​b​ and ​c​ by entering a number then pressing the "=" sign. Scroll down to view the solutions to the equation.

ES models

  1. Rewrite the Equation

  2. Rewrite the equation into standard form, if necessary.

  3. Press Mode, Then 5

  4. Press the "Mode" key followed by "5" to enter the equation calculation mode.

  5. Press 3

  6. Press "3" to select to solve a quadratic equation. This will take you to the coefficient editor screen.

  7. Input Your Values

  8. Input the values of ​a​, ​b​ and ​c​ into the appropriate cells.

  9. Solve

  10. Press the "=" button to see the solution to the equation. If additional solutions are available they will be displayed after more presses of the "=" button. You can also use the up and down arrow keys to scroll between solutions.


    • Not all the ES and MS models have the equation feature. Consult your user guide.


About the Author

Based in London, Anthony Thompson originally worked in the financial sector but has been writing professionally since 1992. The former editor of a monthly computing and technology magazine, his work has appeared in The Guardian, GQ and Time Out.