SOLUTION: The sum of the lengths of any two sides of a triangle must be greater than the third side. If a triangle has one side that is 17 inches and a second side that is 1 inch less than t

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Question 1016849: The sum of the lengths of any two sides of a triangle must be greater than the third side. If a triangle has one side that is 17 inches and a second side that is 1 inch less than twice the third side, what are the possible lengths for the second and third sides?
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
Let s%5B1%5D+=+17, and s%5B2%5D+=+2s%5B3%5D-1
Case 1: s%5B1%5D+%2B+s%5B2%5D+%3E+s%5B3%5D doesn't give any insight, since it reduces to s%5B3%5D+%3E+-16, which is always true.
Case 2: s%5B1%5D+%2B+s%5B3%5D+%3E+s%5B2%5D will lead, upon the proper substitution, to 17+%2B+s%5B3%5D+%3E+2s%5B3%5D-1, or 18+%3E+s%5B3%5D
Case 3: s%5B3%5D+%2B+s%5B2%5D+%3E+s%5B1%5D leads to 2s%5B3%5D-1%2Bs%5B3%5D+%3E17, or
3s%5B3%5D+%3E+18, or s%5B3%5D+%3E+6
Hence, 18+%3E+s%5B3%5D+%3E+6.
Now s%5B3%5D+=+%28s%5B2%5D%2B1%29%2F2, and so substitution into the last inequality and simplifying yields
35+%3E+s%5B2%5D+%3E+11.