diagonals of a parallelogram bisect each other
or they intersect each other in the halfway
x+4=3y-11-------------------------equation1
2x-1=y-1-------------------------------equation2
mulitply equation 1 to 2
2x+8=6y-22-----------------------equation3
equation2 - equation3
-9=-5y +21
5y=30
y=6
then x= 3
now PT=2x-1=5
TR=y-1=5
ST=3y-11=7
TQ=x+4=3+4=7