SOLUTION: Solve the following problem using "Complete the Square" Method 2x^2+14x-1=0

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Question 445023: Solve the following problem using "Complete the Square" Method
2x^2+14x-1=0

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the following problem using "Complete the Square" Method
2x^2+14x-1=0
..
2x^2+14x-1=0
move constant to right side
2x^2+14x=1
factor out 2 on left side so x^2 has a coefficient of 1. To complete the square, take 1/2 the coefficient of x then square it (7/2)^2=49/4
2(x^2+7x+49/4)=1+49/2 (since I added 2*49/4 to complete the square, I must also add it to the right side.)
2(x^2+7x+49/4)=(2/2)+(49/2)=51/2
divide both sides by 2
(x+7/2)^2=51/4
take sqrt of both sides
x+7/2=+-sqrt(51/4)=+-√51/2
x=-7/2+-√51/2
x=(-7-√51)/2=-7.07
or
x=(-7+√51/2=.0707