SOLUTION: Im not sure how to do this problem Graph: {{{y=x^2-4x+1}}}

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Question 19436: Im not sure how to do this problem
Graph: y=x%5E2-4x%2B1
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
You can find the x-coordinate of the vertex of this parabola from: x+=+-b%2F2a
x+=+-%28-4%29%2F2 = 2
The y-coordinate is found by substituting this value of x (2) into the quadratic equation and solving for y:
y+=+2%5E2+-+4%282%29+%2B+1
y+=+4+-+8+%2B+1
y+=+-3
The vertex is at (2, -3)
Then you could find the x-intercepts (there will be two of 'em) by letting y = 0 and solving for the roots.
x%5E2+-+4x+%2B+1+=+0 Use the quadratic formula to solve: x+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F2a
x+=+%28-%28-4%29%2B-sqrt%28%28-4%29%5E2+-+4%281%29%281%29%29%29%2F2%281%29
x+=+%284%2B-sqrt%2812%29%29%2F2
x+=+2%2Bsqrt%283%29 and x+=+2-sqrt%283%29
Here's what the graph will look like:
graph%28300%2C200%2C-10%2C10%2C-10%2C10%2Cx%5E2-4x%2B1%29