similarity and congruence
What if the triangles are flipped, so one has a 41° on the
right and the other has a 41° angle on left? Are they similar?
A:As long as you can spot another angle which is in
both triangles then yes, they’re definitely similar. Similarity is
maintained even if your shape is reflected or rotated.
Isn’t using similarity kind of like cheating? Shouldn’t I
be working out all the angles individually?
A:Cheating? We like to think of it as working smarter rather
than harder. It does save you plenty of leg work though. Most
geometry teachers will be more impressed by use of similarity
than repetitive calculations anyway—just make sure to make a
note on your work that you used similarity.
How many repeated angles are there in total on this diagram,
including the ones you’ve already marked plus the angles a
through i? (Count each value once—if it’s repeated don’t count it
This corner a
you are here 4 63