Let S be the surface given by the equation 9x^2 + y^2 − z^2 − 2y + 2z = 1, Show that the straight line r(t) = <1, 1, 1> + t<1, 0, 0> is normal to the surface S at the points of intersection.(adsbygoogle = window.adsbygoogle || []).push({});

I set both equations equal to each other and I found their points of intersection are (1/3,1,1) and (-1/3,1,1). But I don't know where to go from there.

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# Multivariable Calculus

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