SOLUTION: Please solve x2+7x-2=0. Not sure if I got the right answer.

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Question 274057: Please solve x2+7x-2=0. Not sure if I got the right answer.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
x^2 + 7x - 2 = 0

a = 1
b = 7
c = -2

(-b +/- sqrt(b^2-4ac))/2a becomes:

(-7 +/- sqrt(49-(-8)))/2 which becomes:

(-7 +/- sqrt(57)/2 which becomes:

(-7 +/- 7.549834435))/2 which becomes:

x = .274917218

or:

x = -7.274917218

graph of your equation looks like this:

graph+%28600%2C600%2C-10%2C10%2C-20%2C10%2Cx%5E2+%2B+7x+-+2%29

Since the graph crosses the x-axis at approximately the values calculated, then it looks like we're good.