Answer: 7 < x < 29
------------------------------------------------
Explanation:
Let
a = 11
b = 18
c = x
be the three sides of the triangle
It turns out that if you know the two sides (a=11 and b=18) then you can figure out the range for the third side (c=x) using this inequality
b-a < x < b+a
Notice how 'b' is the larger value
So we can say,
b-a < x < b+a
18-11 < x < 18+11
7 < x < 29
Therefore x can be between 7 and 29 excluding both endpoints
The value of x cannot be 7 or a triangle won't form (instead a straight line will)
The value of x cannot be 29 or a triangle won't form (instead a straight line will)
