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Solve x2 + 12x + 6 = 0 using the completing-the-square method.

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X^2+12x+6=0 subtract 6 from both sides...

x^2+12x=-6 halve linear coefficient, square it, and add it to both sides...

x^2+12x+36=30 now the left side is a perfect square...

(x+6)^2=30 take square root of both sides...

x+6=30^(1/2) subtract 6 from both sides...

x=-6-30^(1/2) and -6+30^(1/2)

User Darrickc
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Solving the quadratic equation x² + 12x + 6 = 0 by using the completing-the-square method, x = - 6 ± √30

To solve x² + 12x + 6 = 0 by using the completing-the-square method, we proceed as follows.

Since we have the quadratic equation x² + 12x + 6 = 0, to solve by completing the square, we rewrite the equation as

x² + 12x + 6 = 0

x² + 12x = - 6

Next, we add the square of half the coefficient of x to both sides. So, we have that

x² + 12x + (12/2)² = - 6 + (12/2)²

x² + 12x + 6² = - 6 + 6²

(x + 6)² = - 6 + 36

(x + 6)² = 30

Now, taking the square root of both sides, we have that

(x + 6)² = 30

√(x + 6)² = ±√30

x + 6 = ±√30

x = - 6 ± √30

So, the value of x = - 6 ± √30.

User Simon PA
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