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# Triangles watch

1. Hey guys, ive been given a non right angled triangle and it has the lengths 30 and 50 (dont matter about units) with a 45 degree angle enclosed how would i find out the other two angles knowing this information? Thanks.
2. use the cosine rule
3. (Original post by Kolya)
use the cosine rule
is there no other shorter method? because im pretty sure my teacher didnt use that method and its very long using the cosine rule lol
4. (Original post by JBKProductions)
is there no other shorter method? because im pretty sure my teacher didnt use that method and its very long using the cosine rule lol
Didn't take me more than a couple of minutes...
5. (Original post by Kolya)
Didn't take me more than a couple of minutes...
lol well there are shorter methods then using the cosine rule and my teacher got the answer 81 degrees so im not sure how he got that answer he doesnt mention which angle he calculated but thats his answer
6. (Original post by JBKProductions)
lol well there are shorter methods then using the cosine rule and my teacher got the answer 81 degrees so im not sure how he got that answer he doesnt mention which angle he calculated but thats his answer
considering the correct answer is 81.38677644..., i think you were dreaming.
7. (Original post by Chewwy)
considering the correct answer is 81.38677644..., i think you were dreaming.
well obviously he rounded the answer lol but i still dont know how he worked it out
8. (Original post by JBKProductions)
well obviously he rounded the answer lol but i still dont know how he worked it out
obviously. my point is there is no way he could have arrive at such an answer without doing a very simple calculation like the cosine rule.
9. (Original post by Chewwy)
obviously. my point is there is no way he could have arrive at such an answer without doing a very simple calculation like the cosine rule.
but i did the consine rule and still didnt get that answer unless im doing it wrong
10. (Original post by JBKProductions)
but i did the consine rule and still didnt get that answer unless im doing it wrong
You're doing it wrong.
11. (Original post by Kolya)
You're doing it wrong.
the answer i keep getting is 98 degrees and 36 degrees (both been rounded) and i just cant seem to get the answer 81 degrees

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