SOLUTION: I'm so lost with this. Please help!!! find the vertex. f(x)= 5(x+ 1/4)^2+19

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Question 312004: I'm so lost with this. Please help!!!
find the vertex. f(x)= 5(x+ 1/4)^2+19

Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
%22f%28x%29%22=+5%28x%2B+1%2F4%29%5E2%2B19
You must memorize the standard equation of a parabola, which is:
%22f%28x%29%22=a%28x-h%29%5E2%2Bk
learn how to compare your equation with that:
%22f%28x%29%22=+5%28x%2B+1%2F4%29%5E2%2B19
And see that a=5, h=-1%2F4, k=19
You must also learn that the vertex is the point (h,k), which is
%22%28%22-1%2F4%22%2C%2219%22%29%22
and that since a, which equals 5 is a positive number,
the graph opens upward.
To check:
%22f%28x%29%22 means the same as y, so find
some points for:
y=+5%28x%2B+1%2F4%29%5E2%2B19
substitute x=-4, get y=89.3
substitute x=-3, get y=56.3
substitute x=-2, get y=34.3
substitute x=-1, get y=21.8
substitute x=0, get y=19.3
substitute x=1, get y=28.8
substitute x=2, get y=44.3
substitute x=3, get y=71.8

graph%28400%2C400%2C-4%2C4%2C-100%2C100%2C+5%28x%2B1%2F4%29%5E2%2B19%29
And it looks like the graph of its vertex (turning point) is:
is %22%28%22-1%2F4%22%2C%2219%22%29%22
Edwin