SOLUTION: 7x2 + 6x + 6 = 0

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Question 1205826: 7x2 + 6x + 6 = 0
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
say exactly what help you need.

Solve equation using factoring?

%287x%2Bsomething%29%28x%2Bsomethingelse%29
try checking 1 and 6, and 2 and 3.

%287x%2B2%29%28x%2B3%29
7x%5E2%2B2x%2B21x%2B6
that does not work.

%287x%2B3%29%28x%2B2%29
7x%5E2%2B3x%2B14x%2B6
that does not work.

%287x%2B6%29%28x%2B1%29
137 on the x.
That doesn't work.

(7x+1)(x+6)
43x this does not work.

check: discriminant is 6%5E2-4%2A7%2A6=36-28%2A6=-132.
Use general solution formula for quadratic equation.

Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!
.

The discriminant of this equation is negative

    d = b%5E2+-+4ac = %28-6+%29%5E2+-+4%2A7%2A6 = 36 - 4*7*6 = -132.


Therefore, the given equation does not have real roots, at all.


It has two roots in complex numbers, but not in real domain.


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    - Introduction into Quadratic Equations
    - PROOF of quadratic formula by completing the square
    - HOW TO complete the square - Learning by examples
    - HOW TO solve quadratic equation by completing the square - Learning by examples
    - Solving quadratic equations without quadratic formula
in this site.

You will find there many problems, solved using the quadratic formula, completing the square and factoring.

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