In order to find the vector that points from A to B we need to subtract each component of A from the corresponding component of B, according to the formula:
v(a→b)=(b1−a1,b2−a2)
In this case we have :
v(a→b)=(−5−(−8),3−(−1))
v(a→b)=(3,4)
To find the magnitude we use the formula:
||v|= √(v1^2)+(v1^2)
So:
||v|= √(32)+(42)
||v|= √9+16
||v|= √25
||v|= 5