Answers:
- Problem 15) RS, RT , ST
- Problem 16) BD, CD, BC
The side lengths are sorted from shortest to longest.
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Step-by-step explanation:
For any triangle, the smallest side is opposite the smallest angle. Similarly, the largest side is opposite the largest angle.
With this in mind, for problem 15, the smallest side is side RS, due to angle T = 50 being the smallest angle. We don't know the value of side RS (nor the other sides so we can numerically compare them), but we don't need this info since the rule mentioned in the first paragraph is sufficient. You could use the law of cosines to help confirm the rule is true.
Also for problem 15, the longest side is side ST. This is because the opposite angle to this side is R = 70, which is the largest angle of the trio.
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In problem 16, the shortest and longest sides are BD and BC respectively. This is because C = 50 and D = 70 are the smallest and largest angles (in that order) and these angles are opposite the mentioned sides in bold.