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Solve each expression by completing the square. x^2+6x=9

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x^2+6x=9

To create a trinomial square on the left side of the equation, you have to find a value that is equal to the square of half of 9.

(9/2)^2=(3)^2

Then, add this therm to each side of the equation.

x^2+6x+(3)^2=9+(3)^2

Simplifying that equation:

x^2+6x+9=18

Factor the perfect trinomial square into (x+3)^2

(x+3)^2=18

To solve the equation for x, you have to take the square root of each side of the equation:

(x+3)^(2*1/2)=18^1/2

Solve each expression by completing the square. x^2+6x=9-example-1
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