There appears to be an error in your calculations or transcription of them.

Specifically, the sign of the 

y2
 component of equation 1, changes between the original form 
    (x-1)2 + y2 = m(z - h1)2
___________^

and it's expansion: 

    x2 - 2x + 1 - y2 = m(z2 - 2zh1 + h12)
________________^

I don't follow the steps you used in the next stage of the reduction, (Eq.2 - Eq.1)/m, so I am unable to filter the correction through the rest of the workings.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^5: OT:Math problem: Grids and conical sections. by BrowserUk
in thread OT:Math problem: Grids and conical sections. by BrowserUk

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