SOLUTION: I haven't been able to figure out the answer. How do I solve the following problem: x^2 + 3x + 1

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Question 150465: I haven't been able to figure out the answer. How do I solve the following problem:
x^2 + 3x + 1
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
I'm assuming that you mean x%5E2%2B3x%2B1=0


x%5E2%2B3x%2B1=0 Start with the given equation.


Let's use the quadratic formula to solve for x


x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29 Start with the quadratic formula


x+=+%28-%283%29+%2B-+sqrt%28+%283%29%5E2-4%281%29%281%29+%29%29%2F%282%281%29%29 Plug in a=1, b=3, and c=1


x+=+%28-3+%2B-+sqrt%28+9-4%281%29%281%29+%29%29%2F%282%281%29%29 Square 3 to get 9.


x+=+%28-3+%2B-+sqrt%28+9-4+%29%29%2F%282%281%29%29 Multiply 4%281%29%281%29 to get 4


x+=+%28-3+%2B-+sqrt%28+5+%29%29%2F%282%281%29%29 Subtract 4 from 9 to get 5


x+=+%28-3+%2B-+sqrt%28+5+%29%29%2F%282%29 Multiply 2 and 1 to get 2.


x+=+%28-3%2Bsqrt%285%29%29%2F%282%29 or x+=+%28-3-sqrt%285%29%29%2F%282%29 Break up the expression.


So our answers are x+=+%28-3%2Bsqrt%285%29%29%2F%282%29 or x+=+%28-3-sqrt%285%29%29%2F%282%29


which approximate to x=-0.382 or x=-2.618