1. Introductory Algebra Glossary

2. quadratic equation
A quadratic equation is an equation that can be written in the form ax2 + bx + c = 0, where a, b, and c are real numbers, with a 0.

3. The quantity under the radical in the quadratic formula, b2 - 4ac.
discriminant
The quantity under the radical in the quadratic formula, b2 - 4ac.

4. complex number
Any number that can be written in the form a + bi, where a and b are real numbers.

5. imaginary number
A complex number a + bi
with b  0.

6. The real part of a complex
number a + bi is a.

7. imaginary part
The imaginary part of the
complex number a + bi is b.

8. standard form of a complex number
The standard form of a
complex number is a + bi.

9. conjugate of a complex number
The conjugate of a complex
number a + bi is a - bi.

10. parabola
The graph of a second-degree (quadratic) equation in two variables is called a parabola.

11. parabola
The graph of a second-degree (quadratic) equation in two variables is called a parabola.

12. axis (axis of symmetry)
The axis of a parabola is the vertical or horizontal line through the vertex of the parabola.

13. quadratic function
A function defined by an equation of the form f(x) = ax2 + bx + c, for real numbers a, b, and c, with a 0.