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solve x^2 6x = 7 by completing the square. which is the solution set of the equation? a. {–7, 1} d. {1, 7}

User JARRRRG
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1 Answer

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x^2+6x=7
take 1/2 of 6 and square it (3^2=9)
add that to both sides
x^2+6x+9=7+9
x^2+6x+9=16
factor perfect square
(x+3)^2=16
square root both sides
remembe to take the positive and negative square roots
x+3=+/-4

minus 3 from both side
x=+/-4-3
x=-7 or 1

A is answer

User Joelhardi
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