SOLUTION: We are asked to graph the following quadradic equation -f(x)=X^2-3x+1. AS I graph it the parabola opens up, 3 spaces up and is moved over 1 space to the right. However accordin

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Question 57272This question is from textbook
: We are asked to graph the following quadradic equation -f(x)=X^2-3x+1.
AS I graph it the parabola opens up, 3 spaces up and is moved over 1 space to the right. However according to the book it opens down and over 1 and up the y-axis 3 spaces. If X^2 is positive I thought it opened up?!?! where am I going wrong or what do I not understand?? Any help will be appreciated on this.
Thanks in advance.
This question is from textbook

Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
-f(x)=X^2-3x+1.
You are given the formula for negative f(x)
If you multiply each side by minus-one you
will get:
f(x)=-x^2+3x+1
Now you should see that it opens down because
of the negative coefficient of x^2
If you complete the square you get:
y-1+?=-(x^2-3x+?
y-1-(3/2)^2=-(x^2-3x+(3/2)^2)
y-(13/4)=-(x-(3/2))^2
So the vertex is at (3/2,13,4)
Hope this helps.
cheers,
Stan H.

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