# SOLUTION: Please help me solve this Quadratic equation. 9x^2+6x-4=0 I have solved it down to -6 sqrt 180 / 18. this is also the same as your sight gave me, but the answer key says t

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9x^2+6x-4=0
I have solved it down to -6 sqrt 180 / 18.
this is also the same as your sight gave me, but the answer key says this.
-1 sqrt 5 / 5

Found 3 solutions by brich, drj, edjones:
You can put this solution on YOUR website!
Do you know the quadratic formula?
It appears that you do.
your sqr_root(180) reduces to 6sqr_root(5) by the way
so now you have:
[-6(+/-)6sqr_root(5)]/18
pull/factor a 6 out of the numerator
6[-1(+/-)sqr_root(5)]/18
6/18 reduces to 1/3
so the final answer i'm coming up with and you seem to already have is:
[-1(+/-)sqr_root(5)]/3
I appears as if the answer key is incorrect
Your answer appears correct but make sure you simplify like I pointed out
That all
Let me know if you are still confused

You can put this solution on YOUR website!

 Solved by pluggable solver: SOLVE quadratic equation with variable Quadratic equation (in our case ) has the following solutons: For these solutions to exist, the discriminant should not be a negative number. First, we need to compute the discriminant : . Discriminant d=180 is greater than zero. That means that there are two solutions: . Quadratic expression can be factored: Again, the answer is: 0.412022659166597, -1.07868932583326. Here's your graph:

and

So, you are in the right track.

I hope the above steps were helpful.

Respectfully,
Dr J