Answer:
Hence as long as x > 2/3, we can form a triangle from the three given sides.
Step-by-step explanation:
Given:
Length of 3 sides of triangle are 
Solution:
From the length of the 2nd side 4x, we know that x > 0
Let this be 1 st statement.
Now from the triangle inequality we can say that;

No new information from this because of the 1st statement above.
Also,

Lastly,

and again no new information is obtained from this inequality.
Hence as long as x > 2/3, we can form a triangle from the three given sides.