The length of the blue line segment is definitely 8. from the diagram it is observed that the red line segment is the longest part of the whole diagram is 14 while the transverse axis is the short part of the the whole diagram is 6 hence the blue line segment has to be 8 this is because
The blue line segment is neither longer than the red line segment which has a value of 14 nor is it shorter than the transverse axis which is 6. from this simple logical statement and from the diagram observation the length of the blue line segment can't be longer than the red line segment and as well it can't be shorter than the transverse axis .
