Now consider a situation that a
girl moves from A to B and then from B to C
(Fig 10 7) The net displacement made by the girl from
point A to the point C, is given by the vector AC
uuur  and
expressed as
AC
uuur  = AB
BC
+
uuur
uuur
This is known as the triangle law of vector addition In general, if we have two vectors ar  and b
r
 (Fig 10