Show that the locus of the mid-point of the segment intercepted between the axes of the variable line `xcosalpha+ysinalpha = p` then `1/(x^2)+1/(y^2)=4/(p^2),` where `p` is a constant.

Explanation

`xcosalpha+ysinalpha=p`

`put y=0`

`xcosalpha=p`

`x=p/cosalpha`

`put x=0`

`ysinalpha=p`

`y=p/sinalpha`

`h=p/(2cosalpha)`

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