SOLUTION: Complete the square. x^2 - 2x= 30

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Question 482676: Complete the square. x^2 - 2x= 30
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2+-2x=+30...take half of the coefficient (don't forget the sign!) of the x-term which is half+of+%7B%7B%7B-2 is -1,square it (which will be %28-1%29%5E2=1, and add this square to both sides of the equation
x%5E2+-2x%2B1=+30%2B1
%28x-1%29%5E2=31
x-1=+-sqrt%2831%29
x-1=+-5.57
solutions:
x-1=5.57 or x-1=-5.57

if x-1=5.57...->...x=5.57%2B1..->...x=6.57
or
if x-1=-5.57...->...x=-5.57%2B1..->...x=-4.57


check:
%286.57%29%5E2+-2%286.57%29=+30
43.1649+-13.14=+30
30.0249=+30
30=+30