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Does This Make a Triangle? — Mixed

Check exactly one triangle, more than one, or none, then justify it.

ExampleA triangle is to have sides of 7 cm, 11 cm and 15 cm.
How many such triangles can be drawn?
exactly onemore than onenone
Why: Check the two shorter sides against the longest: 7 + 11 = 18, which is more than 15, so the sides can close up. Three fixed side lengths lock every angle too, so any triangle drawn from them is the same shape and size (SSS).
  1. 1.A triangle is to have sides of 9 cm, 9 cm and 9 cm.
    How many such triangles can be drawn?
    exactly onemore than onenone
    Why?
  2. 2.A triangle is to have angles of 42°, 73° and 65°.
    How many such triangles can be drawn?
    exactly onemore than onenone
    Why?
  3. 3.A triangle is to have two sides of 7 cm and 6 cm, with an angle of 90° opposite the 7 cm side.
    How many such triangles can be drawn?
    exactly onemore than onenone
    Why?
  4. 4.A triangle is to have sides of 5 cm, 6 cm and 8 cm.
    How many such triangles can be drawn?
    exactly onemore than onenone
    Why?
  5. 5.A triangle is to have sides of 4 cm, 5 cm and 11 cm.
    How many such triangles can be drawn?
    exactly onemore than onenone
    Why?