Using Show to place a ParametricPlot on a LogLog scale

I wish to have a few plots on the same graph: ListLogLogPlot, LogLogPlot and a ParametricPlot drawing lines perpendicular to the x-axis. The problem is however that ParametricPlot doesn't seem to have the LogLog equivalent, as the other Plot functions do, and Show does not combine non-LogLog plots with LogLog plots, even when they coincide, eg.:

Show[LogLogPlot[x^4, {x,10^(-10),10^10}], Plot[x^5, {x,10^(-10),10^10}]]


should theoretically show two straight lines, but shows only one. Is there a way to combine such graphics without resolving to using non-LogLog plots?

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@Öskå Well, it was just an example... Anyway thanks for pointing it out! –  Lurco Jul 10 '14 at 11:15

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Wow, it works! I thought I tested out this possibility as well... Anyway it makes sense $-$ thanks! –  Lurco Jul 11 '14 at 18:21