SOLUTION: Find the x-intercepts. y=x^2 -7x +11. I am not understanding how to do this and need some assistance. Thanks.

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Question 76796: Find the x-intercepts. y=x^2 -7x +11.
I am not understanding how to do this and need some assistance. Thanks.
Answer by chitra(359) About Me  (Show Source):
You can put this solution on YOUR website!
The given equation is:

+y+=+x%5E2++-+7x++%2B+11+

To find the x-intercepts we substitute y = 0, which then gives us a quadratic in x.

That is x%5E2+-+7x+%2B+11+=+0+

This can be solved by using the quadratic formula.

x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

Substittuting for the values, we get:

x+=+%287+%2B-+sqrt%28+7%5E2+-+4%2A%281%29%2A%2811%29%29%29%2F%282%2A1%29

x+=+%287+%2B-+sqrt%2849+-+44%29%2F2%29

x+=+%28+7+%2B-+sqrt%285%29%2F2%29

Hence, the x intercepts are:


x+=+%287+%2B+sqrt%285%29%29%2F2%29+ and x+=+%287+-+sqrt%285%29%29%2F2%29+


Hence, the solutions.