SOLUTION: How do I find the exact and approximate solutions of this equation? x^2+3x-5=0

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Question 455105: How do I find the exact and approximate solutions of this equation? x^2+3x-5=0
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
You can "complete the square":
x^2+3x-5=0
x^2+3x=5
x^2+3x + 9/4 = 5 + 9/4
x^2+3x + 9/4 = 20/4 + 9/4
x^2+3x + 9/4 = 29/4
(x+3/2)(x+3/2) = 29/4
(x+3/2)^2 = 29/4
x+3/2 = sqrt(29/4)
x+3/2 = sqrt(29)/2
x = sqrt(29)/2 - 3/2
x = (sqrt(29)- 3)/2
or
x = %28sqrt%2829%29-+3%29%2F2 Exact answer
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x = 1.193 Approximate answer