SOLUTION: which is an equation of the axis of symmetry of the grapd y=x^2-4x+1?

Algebra ->  Graphs -> SOLUTION: which is an equation of the axis of symmetry of the grapd y=x^2-4x+1?      Log On


   

Question 77256: which is an equation of the axis of symmetry of the grapd y=x^2-4x+1?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
y+=+x%5E2+-+4x+%2B+1
This can be solved by completing the square (add 4 and subtract 4)
y+=+x%5E2+-4x+%2B+4+%2B+1+-+4
y+=+%28x+-+2%29%5E2+-+3
The axis of symmetry is halfway between the 2 roots (where y = 0)
What values of x makes y = 0?
x+=+2+%2B-sqrt%283%29 make y = 0
To find the point halfway between
x+=+2+%2B+sqrt%283%29 and
x+=+2+-+sqrt%283%29
add them and divide by 2
The answer is x = 2
That is the equation of the line