TI-84 Plus Quadratic Solver
Solve quadratic equations ($ax^2 + bx + c = 0$) instantly using the logic of the Texas Instruments TI-84 Plus.
Enter values for a, b, and c to solve for x.
How to Use the Quadratic Formula
The Texas Instruments TI-84 Plus is a powerful tool for algebra students. One of its most frequently used features is the built-in polynomial solver, which finds the roots of quadratic equations. This web tool replicates that functionality using the standard quadratic formula:
$x = \frac{-b \pm \sqrt{b^2 – 4ac}}{2a}$
Understanding the Discriminant
The part of the formula under the square root ($b^2 – 4ac$) is called the discriminant. On the TI-84 Plus, this value determines the type of answer you will receive:
- Positive Discriminant: There are two real solutions. The graph crosses the x-axis at two distinct points.
- Zero Discriminant: There is one real solution. The graph touches the x-axis at exactly one point (the vertex).
- Negative Discriminant: There are two complex solutions. The graph does not touch the x-axis.
Step-by-Step TI-84 Plus Instructions
If you are using the physical device, follow these steps to verify the results from the calculator above:
- Press the [MATH] key.
- Scroll down to highlight 0: Solver… and press [ENTER].
- Ensure the equation is set to
0=or input your specific equation (e.g., $X^2+5X+6$). - Press [ALPHA] then [ENTER] (SOLVE) to view the roots.