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Janie
06-27-2006, 05:01 PM
Solve the following quadratic equation

x^2 + 9x-31=0

(x + 3x-30) (x + 3x-1)=0

Is this right?

jonboy
06-27-2006, 05:08 PM
Solve by using the Quadratic Formula, since no numbers multiply to give you -31 and add up to 9. Do not factor. Just use the Quadratic Formula:
http://media.nasaexplores.com/lessons/01-003/images/quadform.gif

Denis
06-27-2006, 05:27 PM
Solve the following quadratic equation
x^2 + 9x-31=0
(x + 3x-30) (x + 3x-1)=0
Is this right?
Sorry Janie, but you need to get back to basics...did you miss a lot of math class time?

tkhunny
06-27-2006, 05:29 PM
Solve the following quadratic equation

x^2 + 9x-31=0

(x + 3x-30) (x + 3x-1)=0

Is this right?Have you EVER seen an example that came out like that? Ever?

First, what's the point of x + 3x? Isn't that 4x? Now it makes no sense.
Second, I suspect you have successfully factored some other problem. I expect it looked like this (x+___)(x-___), where the blanks are some value and the operations could be addition or subtraction. That's what this one should look like IF it can be factored. Failing that, there are other methods -- jonboy suggested one.