Calculating Moment of Inertia for Combined Shapes

[Hayden Leete]

https://scontent-syd1-1.xx.fbcdn.net/hphotos-xfl1/v/t34.0-12/13015003_664975026975127_933044449_n.png?oh=0259712996d9a6dde812f6d8886f56b9&oe=5715CA95
So, it's straight forward enough to calculate the moment of inertia of basic planes with evenly distributed mass, but if I were to say glue the red and green plane together, how would I find the moment of inertia of the blue shape?

 

[Doc Al]

how would I find the moment of inertia of the blue shape?

About what axis?

You can find the moment of inertia of each piece about the axis of choice, then just add them. (You'll need the parallel axis theorem.)

 

[Hayden Leete]

About what axis?

You can find the moment of inertia of each piece about the axis of choice, then just add them. (You'll need the parallel axis theorem.)

probably should have specified, the z axis, or the axis perpendicular to the plane. the axis of choice is the blue COM, and I don't know how to find the moment of inertia of each shape except with central axes (I don't know much in the world of rotational inertia)

 

[Hayden Leete]

actually you know what, through more googling and researching stuffs, I've figured it out. I've been trying to find somewhere to explain this to me for a while now, but I didn't know exactly what to search for until your reply, so thanks for that