SOLUTION: can someone please help me with this solve by using the quadratic formula and prove your answer is correct by checking, ok im not so sure what the quadratic formula is can some

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Question 797226: can someone please help me with this
solve by using the quadratic formula and prove your answer is correct by checking, ok im not so sure what the quadratic formula is can someone show me how to do this step by step and explain it to me thank you

X^2+9=0
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
X^2+9=0
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B0x%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=%280%29%5E2-4%2A1%2A9=-36.

The discriminant -36 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 -36 is + or - sqrt%28+36%29+=+6.

The solution is x%5B12%5D+=+%28-0%2B-i%2Asqrt%28+-36+%29%29%2F2%5C1+=++%28-0%2B-i%2A6%29%2F2%5C1+, or
Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B0%2Ax%2B9+%29