SOLUTION: Determine the equation of the axis of symmetry for the parabola whose x - intercepts are (-3, 0) and (1,0).

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Question 99654: Determine the equation of the axis of symmetry for the parabola whose x - intercepts are (-3, 0) and (1,0).
Found 2 solutions by stanbon, jim_thompson5910:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Determine the equation of the axis of symmetry for the parabola whose x - intercepts are (-3, 0) and (1,0).
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The axis of symmetry is half-way between the x intercepts.
That would be the line x = -1
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Cheers,
Stan H.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
The axis of symmetry is always the point right in the middle of the two intercepts. That is why it is called the axis of symmetry.


So if we have x-intercepts of -3 and 1, just average them to get the axis of symmetry:


%28-3%2B1%29%2F2=-2%2F2=-1


So the axis of symmetry is x=-1


Notice if we graph a parabola with x-intercepts (-3, 0) and (1,0) we get


graph of the parabola with x-intercepts (-3, 0) and (1,0) with the axis of symmetry x=-1

Notice the vertical line at x=-1 evenly splits the parabola in two