SOLUTION: use the quadratic formula to solve the equation x^2-x=-9 the solution set is {_} T ype an exact answer,using radicals as needed. Express complex numbers in terms of i. Use

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Question 399512: use the quadratic formula to solve the equation
x^2-x=-9
the solution set is {_}
T
ype an exact answer,using radicals as needed. Express complex numbers in terms of i. Use intergers or fractions for any numbers in the expression. Use comas to seperate answers as needed.
Found 2 solutions by Alan3354, josmiceli:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
x^2-x=-9
x%5E2+-+x+%2B+9+=+0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B-1x%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=%28-1%29%5E2-4%2A1%2A9=-35.

The discriminant -35 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 -35 is + or - sqrt%28+35%29+=+5.91607978309962.

The solution is , or
Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-1%2Ax%2B9+%29

Answer by josmiceli(19441) About Me  (Show Source):