Why does the angle at s and the missing angles on both sides suppose to add up to 180? usually 180 is drawn out to be a straight line. Am I missing something here?
what makes you think those angles add to 180?
Ok so this question tests the concept of isosceles triangles, which have two same sides and two same angles. the angle at S and the missing angles on both sides do not add up to 180. However, we can deduce that the missing angles are p on the left side and r on the right side if we use the concept of isosceles triangles (I can go into more detail abt that if you want). taking the big triangle into consideration, we know that p + r + s + the two missing angles at the top = 180. since we know the two missing angles at the top are p and r, we can rewrite as: p+r+p+r+s=180. solving for s, we get 180-2p-2r, and factoring out the 2 we get 180-2(p+r). hope this helps!
Your own math says those two angles +s don’t add to 180. But you got it right!
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