SOLUTION: what is the vertex of -X^2+2x-3

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Question 1189921: what is the vertex of -X^2+2x-3
Found 2 solutions by MathLover1, Boreal:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

the vertex of
-x%5E2%2B2x-3 .........complete square
%28-x%5E2%2B2x%29-3........factor out coefficient -1
-1%28x%5E2-2x%29-3
-%28x%5E2-2x%2Bb%5E2%29-%28-1%2Ab%5E2%29-3.......b=2%2F2=1
-%28x%5E2-2x%2B1%5E2%29%2B1%2A1%5E2-3
-%28x-1%29%5E2%2B1-3
-%28x-1%29%5E2-2

vertex is at: (1,-2)

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
The vertex is where x=-b/2a
this is -2/-2 or +1 for x
when x=1, f(1)=-2
(1, -2)
-
vertex form
-(x^2-2x+3)
complete the square
-(x^2+2x+1)-3+1, the first 1 is negative and the second is positive
-(x-1)^2-2
this is vertex form
the vertex is (1, -2), or (-h, k)
graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C-x%5E2%2B2x-3%29