Answer:
Length = 9 units
Step-by-step explanation:
Length between two points...,
Apply the following formula,
Length = square root of [(difference in x coordinates)^2 + (difference in y coordinates)^2]
Length = square root of [ (4 - 0)^2 + (7 - -1)^2 ]
Length = square root of (80)
Length = 9 units