Question

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

8, 4, 12
8, 4, 12

10, 20, 15
10, 20, 15

20, 10, 30
20, 10, 30

8, 8, 20
8, 8, 20
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1 answer

To determine which set of side lengths can form a triangle, we'll apply the Triangle Inequality Theorem. The theorem states that for any three sides a, b, and c of a triangle, the following must be true:

  1. a+b>c
  2. a+c>b
  3. b+c>a

Let's evaluate each set of side lengths:

  1. 8, 4, 12

    • 8+4=12 (not greater, so fails)
    • 8+12>4 (true)
    • 4+12>8 (true)
    • Does not form a triangle.
  2. 10, 20, 15

    • 10+20=30>15 (true)
    • 10+15=25>20 (true)
    • 20+15=35>10 (true)
    • Forms a triangle.
  3. 20, 10, 30

    • 20+10=30 (not greater, so fails)
    • 20+30>10 (true)
    • 10+30>20 (true)
    • Does not form a triangle.
  4. 8, 8, 20

    • 8+8=16<20 (not greater, so fails)
    • 8+20>8 (true)
    • 8+20>8 (true)
    • Does not form a triangle.

Conclusion: The only set of side lengths that can form a triangle is 10, 20, 15.