SOLUTION: f(x)=1-4x-x^2 Express the quadratic function in standard form

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Question 711569: f(x)=1-4x-x^2
Express the quadratic function in standard form
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
That means, first Complete the Square.

Turn some of the function around some.
f%28x%29=1-4x-x%5E2
f%28x%29=-x%5E2-4x%2B1
Factor a negative 1 from the first two terms,
f%28x%29=%28-1%29%28x%5E2%2B4x%29%2B1

The quantity which will complete the square is %284%2F2%29%5E2=4.
ADD and SUBTRACT 4, but add it inside the parentheses and subtract something related to it outside the parentheses.

%28-1%29%28x%5E2%2B4x%2B4%29%2B1-%28-1%29%284%29
-1%28x%5E2%2B4x%2B4%29%2B5
highlight%28-1%28x%2B2%29%5E2%2B5%29, your standard form expression for your function f(x).