2007-03-12 18:51:34 · 7 answers · asked by Anonymous in Education & Reference ➔ Homework Help
The general form of a quadratic equation is ax²+bx+c. The quadratic formula is defined as "x= (-b± √b²-4ac) / 2a".
If "b" in the equation ax² + bx + c is even, and "d" is half of "b", the following equation "x=(-d± √d²-ac) / a" is also true.
2007-03-12 19:05:58 · answer #1 · answered by Scotty G 2 · 0⤊ 0⤋
Often, the simplest way to solve "ax2 + bx + c = 0" for the value of x is to factor the quadratic, set each factor equal to zero, and then solve each factor. But sometimes the quadratic is too messy, or it doesn't factor at all, or you just don't feel like factoring. So, while factoring may not always be successful, the Quadratic Formula can always find the solution.
The Quadratic Formula uses the "a", "b", and "c" from "ax2 + bx + c", where "a", "b", and "c" are just numbers. The Formula is derived from the process of completing the square, and is formally stated as:
For ax2 + bx + c = 0, the value of x is given by:
Note that, for the Formula to work, you must have "(quadratic) = 0". Note also that the "2a" at the bottom of the Formula is underneath everything above, not just the square root. And don't forget that it's a "2a" under there, not just a "2"! And make sure that you are careful not to drop the square root or the "plus/minus" in the middle of your calculations, or I can guarantee that you will forget to "put them back" on your test, and you'll mess yourself up. And remember that "b2" means "the square of ALL of b, including the sign", so don't leave b2 being negative, even if b is negative, because the square of a negative is a positive.
2007-03-13 01:56:15 · answer #2 · answered by ♥!BabyDoLL!♥ 5 · 0⤊ 1⤋
I';ll say it in figures since it's pretty difficult to type it as it is:
x equals:
The quantity:
-b plus/minus the square root of (b^2 - 4ac)
over
2a
2007-03-13 01:58:25 · answer #3 · answered by Kim 3 · 0⤊ 0⤋
negative b plus minus the square root of b squared minus four a c over 2 a
2007-03-13 01:55:04 · answer #4 · answered by Pop 3 · 1⤊ 0⤋
I will write it out. Negative b, plus or minus all in a radical b squared minus 4ac all over 2b. But, I would use this website instead.
2007-03-13 01:56:34 · answer #5 · answered by ftballtwenty1 4 · 1⤊ 0⤋
ax2 + bx + c = 0
2 means "squared"
2007-03-13 01:56:42 · answer #6 · answered by MaestroB 3 · 0⤊ 1⤋
-b + or- sq.root of b^2-4ac/2b
2007-03-13 06:06:18 · answer #7 · answered by Dave aka Spider Monkey 7 · 0⤊ 0⤋