Question 4531: what are the other ways to find for the vertex
Answer by pushpaharan(47)   (Show Source):
You can put this solution on YOUR website! by compleating the square method.
x^2 -6x-7
x^2 - 6x + 9 -9 -7
(x-2)^2 - 16
vertex = (2,-16)
by factoring - > find the roots-> find axis of symetry by finding average of the roots (x value of vertex) - > by substitute it in the equation find the y value of vertex.
x^2 -6x-7 = (x-7)(x+1)
roots = 7,-1 => axis of sym -> x=(7+-1)/2 = 3
substitute 3^2 - 6*3 -7 = -16
vertex (3,-16)
there are some other methods too.. like partial factoring...
x^2 -6x-7
x(x-6)- 7
the points it will cut the libe y= -7 are 0,6
axis of symetry = (0+6)/2 = 3
substitute.. you will get -16
then vertex (3,-16)
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