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Quadratic equation

A program to calculate and interpret the results of a quadratic equation.

A quadratic equation can be written in the form below.

a.x² + b.x + c = 0

First the discrimant must be calculated:

D = b² - 4.a.c

If the discriminant is below zero, the equation has no solution.

If the discriminant is zero, the equation has a single solution. The solution will be equal to the formula below:

x = (-b) / (2.a)

If the discriminant is above zero, the equation has two solutions. The solutions can be calcultaed by the formulas below:

x₁ = (-b + √(D) ) / (2.a)

x₂ = (-b - √(D) ) / (2.a)

The code in the Texas TI-84 might look like this:

: ClrHome

:

: Prompt A

: Prompt B

: Prompt C

:

: (B*B)-(4*A*C) -> D

:

: Disp "Discriminant:"

: Disp D

:

: If D<0

: Then

: Disp "No solution."

: End

:

: If D=0

: Then

: Disp "1 solution:"

: -B / (2*A) -> E

: Disp E

: End

:

: If D>0

: Then

: Disp "2 solutions:"

: (-B+√(D)) / (2*A) -> E

: (-B-√(D)) / (2*A) -> F

: Disp E

: Disp F

: End

:

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