# Transparency in a 3D plot

How can I make the plane in the first image more like the plane in the second? More transparent, specially. I tried messing with the Opacity and Mesh, to no avail. Can someone help me? (you can disregard the vector completely)

Right now, the code for the first image is:

Show[Plot3D[{Sqrt[x^2 + y^2], -Sqrt[x^2 + y^2]}, {x, -10, 10}, {y, -10, 10},
PlotStyle -> RGBColor[0.86, 0.86, 0., .1], Mesh -> None],
Plot3D[1/5 (3 x + 4 y), {x, -10, 10}, {y, -10, 10},
PlotStyle -> RGBColor[1., 0.9, 0.14], PlotStyle -> Opacity[0.9],
Mesh -> None],
Graphics3D[Arrow[{{0, 0, 0}, {-6, -8, 10}}]],
BoxRatios -> {1, 1, 1}, Boxed -> False, AxesOrigin -> {0, 0, 0}]

-
You're trying to specify PlotStyle twice, which doesn't work (the second one is ignored). Use Directive to combine them instead: PlotStyle -> Directive[RGBColor[1., 0.9, 0.14], Opacity[0.9]] – Rahul Aug 18 '14 at 21:29
Somehow I found myself here, and this 'Directive' did showed up. It sorta worked. Thank you! I think I'm going to delete the question, it was too basic to be here, no? – Ivo Terek Aug 18 '14 at 21:37

Show[
Plot3D[{Sqrt[x^2 + y^2], -Sqrt[x^2 + y^2]}, {x, -10, 10}, {y, -10,
10}, PlotStyle -> RGBColor[0.86, 0.86, 0., .1], Mesh -> None],

Plot3D[1/5 (3 x + 4 y), {x, -10, 10}, {y, -10, 10},
PlotStyle -> Hue[0.3, 0.96, 0.54, 0.7],
MeshStyle -> Directive[Dashed, White, Opacity[.3]]],

Graphics3D[Arrow[{{0, 0, 0}, {-6, -8, 10}}]],

BoxRatios -> {1, 1, 1}, Boxed -> False, AxesOrigin -> {0, 0, 0}]
`

-