Question

which set of side lengths does not form a triangle? all lengths are given in inches. (1 point) 18, 11, 8 9, 17, 11 18, 10, 8 11, 19, 9

Explanation:

Step1: Recall triangle - inequality theorem

The sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

Step2: Check option 18, 11, 8

$11 + 8=19>18$, $18 + 8 = 26>11$, $18+11 = 29>8$. So, it can form a triangle.

Step3: Check option 9, 17, 11

$9 + 11=20>17$, $17 + 11 = 28>9$, $17+9 = 26>11$. So, it can form a triangle.

Step4: Check option 18, 10, 8

$10 + 8=18$, which is not greater than 18. According to the triangle - inequality theorem, this set of side - lengths does not form a triangle.

Step5: Check option 11, 19, 9

$11 + 9=20>19$, $19 + 9 = 28>11$, $19+11 = 30>9$. So, it can form a triangle.

Answer:

18, 10, 8