Assumptions in exams (1 Viewer)

[Durka224]

Basically in order to save time in an exam I'm trying to ascertain what exactly can be assumed as part of a proof in an exam. For example can you assume and write that two triangles are similar without proof particularly if they are like this:



This would be particularly useful for proofs regarding volume questions. Are there any other assumptions such as this that can/can't be made. Thanks.

 

[hscishard]

I don't think you can assume anything. And you don't have enough info to deduce those two triangles are similar since CB and DE are not given to be parallel

 

[Deep Blue]

Like hscishard said, you can't assume anything in MX2.

 

[Durka224]

even given CB and ED are parallel?

 

[D94]

This would be particularly useful for proofs regarding volume questions.

Could you show us an example in Volumes which would require similar triangles? I don't believe I've seen one before.

 

[Durka224]

I dont think there are that many nowadays, but many 80's papers required them. I did a paper (HSC or CSSA i forget) last week that was >1995 that required similar triangles.