These web-based activities were developed, during summer sessions from 1997 through 1999, by students at Mainland High School, located in Daytona Beach, FL. As part of Mainland's CCTT grant, the students were given permission by the book's publisher to convert the ancillary materials of the County's adopted Algebra 1 textbook (Glencoe Algebra 1 — ISBN: 9780028253282) into html format.

Study Guide
Solving Quadratics by Using the Quadratic Formula

The method of completing the square (Section 13-6) can be used to develop a general fromula called the quadratic formula that can be used to solve any quadratic function.
The expression under the radical, b2 - 4ac, is called the discriminant. In order for the roots (aka, positions where the parabola crosses the x-axis) of a quadratic function to be real, the discriminant must be non-negative. If the disciminant is negative, then the parabola NEVER crosses the x-axis.
Example: Use the quadratic formula to solve x2 − 6x − 2 = 0.	The ≈ tell you that the roots are approximately equal to the stated values.
1. 4t2 = 144   −6, 6 2. 2x2 + 9x + 4 = 0   −4, −½ 3. 8x2 + 17x + 2 = 0   −2 −⅛ 4. 3z2 + 5z −2 = 0   −2, ⅓ 5. −2m2 + 8m + 4 = 0   4.45, −0.45 6. x2 + 3x - 2 = 0   0.56, −3.56 7. 2x2 −6x + 4 = 0   1, 2 8. 5x2 + 10 = 15   −1, 1 2y2 −9y −3 = 0   4.81, −0.31

Copyright 1997-1999: html adaptation
Career Connection to Teaching with Technology