Answer:
x = 6
Step-by-step explanation:
Here it's sayin that Q is a point in between the end-points P & R. If we join P & R , it forms a line segment & Q is in the line segment PR. Hence PQ & QR are also line segments which combine to form line segment PR. So ,
PR = PQ + QR
Putting the given values of PQ ,QR & PR
=> 4x - 12 + 2x + 7 = 31
=> 6x - 5 = 31
=> 6x = 31 + 5
= 36
=> x = 36/6 = 6
