First find the distance from (3,0) to (6,1)
We will use the distance formula
d = sqrt( (x2-x1)^2 + ( y2-y1)^2)
= sqrt( ( 6-3)^2 + ( 1-0)^2)
= sqrt( 3^2 + 1^2)
= sqrt( 9+1)
= sqrt(10)
Now we can find the distance between ( 6,1) and (9,0)
We will use the distance formula
d = sqrt( (x2-x1)^2 + ( y2-y1)^2)
= sqrt( ( 9-6)^2 + (0-1)^2)
= sqrt( 3^2+ (-1)^2)
= sqrt( 9+1)
= sqrt(10)
The distance is sqrt(10)