SOLUTION: 9x^2=2x-5 My answer is x=4/3 Is this the correct answer?

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Question 463331: 9x^2=2x-5
My answer is x=4/3
Is this the correct answer?
Found 2 solutions by Alan3354, jorel1380:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
9x^2=2x-5
My answer is x=4/3
Is this the correct answer?
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Sub 4/3 for x and see.
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9*(4/3)^2 =? 2(4/3) - 5
9*16/9 =? 8/3 - 5
16 =? -7/3
I think not.
How did you get 4/3?

Answer by jorel1380(3719) About Me  (Show Source):
You can put this solution on YOUR website!
9x2=2x-5
9x2-2x+5=0
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 9x%5E2%2B-2x%2B5+=+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=%28-2%29%5E2-4%2A9%2A5=-176.

The discriminant -176 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 -176 is + or - sqrt%28+176%29+=+13.2664991614216.

The solution is

Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+9%2Ax%5E2%2B-2%2Ax%2B5+%29