Question

Which of the following sets of numbers could not represent the three sides of a triangle?

Answer 1

The rule is

• Sum of any two sides>Third side

Check third option

• (15,26,42)

`\\ \rm\bull\rightarrowtail 15+26=41<42`

Option C is correct

Answer 2

(15, 26, 42)

Explanation:

Sides of a triangle rule: the sum of the lengths of any two sides of a triangle has to be greater than the length of the third side.

(8, 1, 18)

8 + 11 = 19 > 18

11 + 18 = 29 > 8

8 + 18 = 26 > 11

Therefore, this is a triangle

(6, 9, 12)

6 + 9 = 15 > 12

6 + 12 = 18 > 9

9 + 12 = 21 > 6

Therefore, this is a triangle

(15, 26, 42)

15 + 26 = 41 < 42

15 + 42 = 57 > 26

26 + 42 = 68 > 15

Therefore, this is NOT a triangle

(13, 19, 31)

13 + 19 = 32 > 31

13 + 31 = 44 > 19

19 + 31 = 50 > 13

Therefore, this is a triangle