Which side is longer? And why please?!

Kieran_read

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Kieran_read

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Yes thank you. However what about AC?
 

Subhotosh Khan

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Kieran_read

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I have no idea - I’m sorry. Which is why I’m asking for help.
 

Subhotosh Khan

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Play with the drawing and the given theorem!
 

pka

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I have no idea - I’m sorry. Which is why I’m asking for help.
\(\displaystyle m(\angle DAC)=61^o\) please tell us why that is the case.
 

Kieran_read

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Triangle DAC has base angles of 61 because the 3 angles add up to 360 degrees and the base angles are the same .
Triangle ABC has base angles of 59 degrees for the same reason
 

Dr.Peterson

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Do you see that this leads to the conclusion you want, by the theorem stated in post #2?
 

Kieran_read

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No. I don’t see.

What do you mean the side with the larger angle is longer. This doesn’t make sense.
 

Subhotosh Khan

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No. I don’t see.

What do you mean the side with the larger angle is longer. This doesn’t make sense.
It is not "with" - it is "subtending": .....................edited

the side subtending the larger angle is longer. .....................edited

A translation of that could be:

the side (in a triangle) "opposite to" the larger angle is longer.

Have you taken any formal geometry? This is one of the early theorems!
 

Jomo

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Draw a line through point B that meets line AC at a right angle. Make sure this line you drew goes above point B as well.
Now pick a point W on this line (or several points) below B and draw a line from W to A and other from W to point C. Is the angle at point W smaller or larger than angle B? Now pick a point on the line you drew above point B. Call this point V. Is angle V more or less than angle B? Do you get my drift?
 

hoosie

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