SOLUTION: How do you solve x^2+3x+9

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Question 522500: How do you solve x^2+3x+9
Found 2 solutions by Earlsdon, oberobic:
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve: x%5E2%2B3x%2B9
This is an "expression" and not an "equation".
Expressions are not solvable. If you make this equal to something, like zero, then you would have an equation that could be solved.
Repost this as an equation.

Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
x^2 +3x + 9 = 0 is a quadratic equation, so you can solve it using the quadratic equation.
.
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B3x%2B9+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%283%29%5E2-4%2A1%2A9=-27.

The discriminant -27 is less than zero. That means that there are no solutions among real numbers.

If you are a student of advanced school algebra and are aware about imaginary numbers, read on.


In the field of imaginary numbers, the square root of -27 is + or - sqrt%28+27%29+=+5.19615242270663.

The solution is

Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B3%2Ax%2B9+%29