# tangent planes...Watch

#1
the x,y,z-intercepts of the tangent plane to the surface
(x/a)^2+(y/b)^2+(z/c)^2=1 (a,b,c>0) at the point (x[0],y[0],z[0]) are equal and +ve.
find the point in terms of a,b,c.

I have found the tangent plane is:

2x[0](x-x[0])/a^2 + 2y[0](y-y[0])/b^2 + 2z[0](z-z[0])/c^2 = 0.

then i subbed in x=y=0 to find z intercept etc for the other axis.

equating what i got didnt really help me.

could someone maybe have a go and offer some hints?

thans xxx
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#2
hey guys, i amstill at a loss with this question. any thoughts ?
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#3
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