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booper563
Oct 29, 2008, 02:48 PM
The vertex of a parabola is (1,2). One x intercept is 1+squareroot5. What is the other x intercept? Explain.

Details pleeease

Unknown008
Oct 30, 2008, 03:23 AM
A parabola is symmetric about its vertex. Here, it is on the x-coordinate 1. So, if one of its x-intercept is 0, the other will be 2, since

1-1 = 0 (x-coordinate of vertex - certain number)
1+1 = 2 (x-coordinate of vertex + that same number above)

So, if one of the x-intercepts is 1+\sqrt5, the 'certain number' I included above is \sqrt5. So, now can you find out the other intercept?

If you didn't understand well and need more explanation, post. Yes, I almost forgot, post your answer.