SOLUTION: find the vertex of the parabola y= x^2-2x-1 vertex (?,?)

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Question 212969: find the vertex of the parabola
y= x^2-2x-1
vertex (?,?)
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
Find the vertex of the parabola

y=+x%5E2-2x-1

vertex (?,?)

Let's graph this parabola:


Try this set of x=-2, -1, 0, 1, 2 and substitute into parabola equation.

For example, x=-2, y=(-2)^2-2(-2)-1= 4+4-1=7 point on graph is (-2,7)

One more and then you try, x=-1, y=(-1)^2-2(-1)-1=-1 point on graph is (-1,-1)

graph%28+300%2C+300%2C+-5%2C+5%2C+-15%2C+15%2Cx%5E2-2x-1+%29

Based on the graph the vertex is (1, -2)

Note when we substitute x=1 in

y=1%5E2-2%281%29-1=-2

I hope the above steps were helpful.

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Good luck in your studies!

Respectfully,
Dr J