Answer-
[tex]\boxed{\boxed{NS=4\ units}}[/tex]
Solution-
As LR = QR, so NR is a median to side LQ
NM = ML, so MQ is a median to side ML
NP = PQ, so PL is a median to side NQ
So, S is the centroid of the ΔNLQ
From the properties of centroid we know that the centroid divides each median in a ratio of 2:1
So applying this,
[tex]\Rightarrow NS=2\times SR[/tex]
[tex]\Rightarrow 7x-3=2\times (5x-3)[/tex]
[tex]\Rightarrow 7x-3=10x-6[/tex]
[tex]\Rightarrow 10x-7x=6-3[/tex]
[tex]\Rightarrow 3x=3[/tex]
[tex]\Rightarrow x=1[/tex]
Therefore, [tex]7(1)-3=7-3=4\ units[/tex]
