Answer:
below
Step-by-step explanation:
A triangle can only be a triangle if the two shortest sides add up to be greater than the longest side.
For example on the first one, the segments 1 2 and 3 will not make a triangle as 1 + 2 = 3 and if the two smallest sides of a triangle are equal to the longest side it will not be a triangle at all.
So to make this easy, out of the three numbers given: add the two smallest numbers. This number has to be greater than the third number given, and it cannot be equal.
For question three: 3+9 = 12
And 12 is greater than 11, therefore this can make a triangle.
