SOLUTION: y=x^2-4x-10 i have to do that by completing the square

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Question 960249: y=x^2-4x-10 i have to do that by completing the square
Found 2 solutions by lwsshak3, MathLover1:
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
solve for x by completing the square:
y=x^2-4x-10
x^2-4x-10=0
(x^2-4x+4)=10+4
(x-2)^2=14
x-2=±√14
x=2±√14

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

y=x%5E2-4x-10+...first group first two terms
y=%28x%5E2-4x%29-10+ ...add some number squared in parentheses and deduct it after
y=%28x%5E2-4x%2Bb%5E2%29-b%5E2-10+....recall the rule:%28a-b%29%5E2=a%5E2-2ab%2Bb%5E2
compare to %28x%5E2-4x%2Bb%5E2%29 and you can see that a=1 and 2ab=4=>
2%2A1b=4
2b=4
b=4%2F2
b=2....now add it to your equation y=%28x%5E2-4x%2Bb%5E2%29-b%5E2-10+
y=%28x%5E2-4x%2B2%5E2%29-2%5E2-10+
y=%28x-2%29%5E2-4-10+
y=%28x-2%29%5E2-14+