eliminating parameter in 3d curved line where functions contain a fractional exponent

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I have the following equations which I use to describe a color in three dimensions (x and y are chromaticity coordinates and z is lightness):

$x = \frac{t^{2.4}}{t^{2.4} + (0.4t + 0.6)^{2.4} + 1}$

$y = \frac{1}{t^{2.4} + (0.4t + 0.6)^{2.4} + 1}$

$z = 0.0722 + (0.2126(t^{2.4})) + (0.7152((0.4t + 0.6)^{2.4}))$

where $0 \le t \le 1$

How would I go about eliminating the parameter $t$? The fractional exponent (which represents gamma transformation) seems to make this feat impossible.

Thank you!

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Hint:  divide the first two equations:

$$ t^{2.4} = \frac{x}{y} \tag{1} $$

Invert the second equation, and use $(1)\,$:

$$ (0.4t+0.6)^{2.4} = \frac{1}{y} - t^{2.4}-1 = \frac{1-x}{y} - 1 \tag{2} $$

Substitute $(1)$ and $(2)$ in the third equation to eliminate $t$ and get a relation between $x,y,z\,$.