Problem 10
Answer: 80 degrees
Work Shown: 80-0 = 80
You subtract the values on the protractor where the two angle arms line up.
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Problem 11
Answer: 45 degrees
Work Shown: 45-0 = 45
Same idea as problem 10
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Problem 12
Answer: 83 degrees
Work Shown: 128-45 = 83
Same idea as the others. The arm TS isn't fully on 130 degrees, and it's a bit short of it. It looks to be about 128 degrees or so.
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Problem 13
Answer: 35 degrees
Explanation: Luis forgot to subtract the value of each arm of the angle. So he should have done 80-45 = 35. The answer would be 80 degrees if arm TQ was at 0 degrees (so 80-0 = 80), but instead TQ is at 45 degrees.