Here's the question you clicked on:
windsylph
If A is a subset of C and B is also a subset of C, then is A union B a subset of C also (subset, not a proper subset)? Intuitively, I'd say no, but I could be wrong..?
Wait, I think I'm starting to think otherwise. But okay, I'll wait for your reply.
Haha I think I got it. But okay, I'll still wait for your reply just to confirm.
|dw:1340779359345:dw| As you see, A and B are subsets of C. Their union is the "shaded area". |dw:1340779385082:dw| So yes, their union is still a subset of C! All points belong within it.
That took forever to upload, sorry, ahaha :)
That's alright. Thank you very much :D