Answer:
If in a scatter plot if all the points lie approximately along a straight line than the relationship that describes the relation between variable x and y is called strong linear correlation.
it may be strong positive or strong negative depending whether the relationship is positive ( i.e. y increases with increase in x) or negative ( i.e. y decreases with increase in 'x')
A "perfect" positive correlation means that the dots all lie on the line given that the relationship is positive.