SOLUTION: I am trying to solve a function that I must graph and I am having a problem solivng the equation,the problem is find the h,the x-coordinate of the vertex of this parabola f(x)=x2

Algebra ->  Rational-functions -> SOLUTION: I am trying to solve a function that I must graph and I am having a problem solivng the equation,the problem is find the h,the x-coordinate of the vertex of this parabola f(x)=x2      Log On


   



Question 92312This question is from textbook Blitzer College Algebra
: I am trying to solve a function that I must graph and I am having a problem solivng the equation,the problem is find the h,the x-coordinate of the vertex of this parabola f(x)=x2+4x+1 and then i have to find the h,the x-coordinate of the vertex of this parabola can you help then I have to substitute the two whole number values to the left and right of h into the function to find the corresponding y to do the graph. This question is from textbook Blitzer College Algebra

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=x^2+4x+1
Complete the square on the x terms and keep the equation balanced.
x^2+4x+? = y-1+?
x^2+4x+4) = y-1+4
(x+2)^2 = y+3
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h=-2; k=-3
So the vertex is at (-2,-3)
The axis of symmetry is x=-2
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If x=-1 y = 1-4+1 = -2 giving you point (-1,-2)
If x=-3 y = 9-12+1 = -2 giving you point (-3,-2)
graph%28400%2C300%2C-10%2C10%2C-10%2C10%2Cx%5E2%2B4x%2B1%29
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Cheers,
Stan H.
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