Question

Which of the following sets of numbers could not represent the three sides of a triangle?
Answer
Multiple Choice Answers
left curly bracket, 5, comma, 9, comma, 13, right curly bracket{5,9,13}
left curly bracket, 9, comma, 21, comma, 29, right curly bracket{9,21,29}
left curly bracket, 10, comma, 20, comma, 31, right curly bracket{10,20,31}
left curly bracket, 13, comma, 27, comma, 39, right curly bracket{13,27,39}

Answer 1

{10, 20, 31}

Reason: triangle inequality requires the sum of any two sides be greater than the third. Here 10 + 20 = 30 ≤ 31, so these cannot form a (nondegenerate) triangle.