SOLUTION: complete the square x^2+4x=6 x= ? and ?

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Question 87886: complete the square
x^2+4x=6
x= ? and ?
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B4x=6+

Assuming that the coefficient of x%5E2 is 1, you must take HALF of the x coefficient and SQUARE it, adding this quantity to each side of the equation as follows:
x%5E2+%2B4x+%2B_____=+6+%2B+____ Half of 4 is 2, and 2^2= 4!
x%5E2+%2B4x+%2B4=+6+%2B+4
%28x%2B2%29%5E2+=+10

Take the square root of each side:
+%28x%2B2%29+=+0%2B-+sqrt%2810%29+

Subtract 10 from each side:
x=+-2+%2B-+sqrt%2810%29+

R^2 Retired from SCC