SOLUTION: Explain why x^2+bx-c=0 must have one positive real and one negative real solution when b and c are real numbers and c>0 . For what values of b will x^2+bx+1=0have real solutions

Question 995840: Explain why x^2+bx-c=0 must have one positive real and one negative real solution when b and c are real numbers and c>0 .
For what values of b will x^2+bx+1=0have real solutions? Clearly explain the reasoning you followed to reach your conclusion
Answer by josgarithmetic(39617) (Show Source): You can put this solution on YOUR website!
The first part is wrong. That cannot be justified. An example was already given a few minutes ago.

Use the discriminant for the second question.
--- given equation;
--- the discriminant, using a=1 and c=1;
-
--- discriminant must be non-zero for the original quadratic equation to have real solutions.

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