# (Texas TI-84 Plus) 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 : ``` 