Question

Which dimensions cannot create a triangle?
three angles measuring 10 degrees, 25 degrees, and 145 degrees
three sides measuring 9 m, 15 m, and 9 m
three angles measuring 40 degrees, 70 degrees, and 65 degrees
three sides measuring 6 cm, 8 cm, and 10 cm

Answer 1

Only the three angles 40°, 70°, and 65° cannot form a triangle — their sum is 175°, not 180°.

The others are valid:
- 10°, 25°, 145° sum to 180°.
- Sides 9, 15, 9 satisfy 9+9 > 15.
- Sides 6, 8, 10 satisfy 6+8 > 10 (and 6²+8² = 10², so it's a right triangle).