SOLUTION: Complete the square: {{{ x^2+7x-2=0 }}} {{{ x^2+7x=2 }}}

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Question 800180: Complete the square:
+x%5E2%2B7x-2=0+
+x%5E2%2B7x=2+

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
x^2 +7x -2 = 0
x^2 +7x = 2
now divide the x coefficient by 2, 7/2 and (7/2)^2 = 49/4
add 49/4 to both sides of the =
x^2 +7x +49/4 = 2 +49/4
factor above equation
(x-49/4)^2 = 57/4
take the square root of both sides of =
x -7/2 = (square root(57))/2
x = square root(57))/2 +7/2
x = (square root(57) +7) /2
now
x = (7 + square root(57) / 2 and
x = (7 - square root(57) / 2