Apply the Triangle Inequality Theorem to determine which three side lengths form a triangle.(1 point)

Responses

10, 20, 15
10, 20, 15

8, 8, 20
8, 8, 20

8, 4, 12
8, 4, 12

20, 10, 30
20, 10, 30

1 answer

The Triangle Inequality Theorem states that for any three lengths \( a \), \( b \), and \( c \) to form a triangle, the following conditions must be satisfied:

  1. \( a + b > c \)
  2. \( a + c > b \)
  3. \( b + c > a \)

Let's check each set of side lengths:

  1. 10, 20, 15

    • \( 10 + 20 = 30 > 15 \) (True)
    • \( 10 + 15 = 25 > 20 \) (True)
    • \( 20 + 15 = 35 > 10 \) (True)
    • These can form a triangle.
  2. 8, 8, 20

    • \( 8 + 8 = 16 \not> 20 \) (False)
    • These cannot form a triangle.
  3. 8, 4, 12

    • \( 8 + 4 = 12 \not> 12 \) (False)
    • These cannot form a triangle.
  4. 20, 10, 30

    • \( 20 + 10 = 30 \not> 30 \) (False)
    • These cannot form a triangle.

Based on the evaluations, the only set of lengths that can form a triangle is 10, 20, 15.