Question 551494
At any given time if you draw a line bewteen chris & pamela with the starting point it will be a right triangle

d=rt
after 3 hours chris will be 120 kms from starting point
after 4 hours pamela will be 180 kms from starting point


Pythagoras theorem
The distance between them is the hypotenuse

Hypotenuse ^2= leg1^2+leg2^2						
						
leg1 = 	120	m				
Leg2^2=	180	m				
						
hypotenuse ^2=	120	^2	+	180	^2	
hypotenuse ^2=	14400	+	32400			
hypotenuse ^2=	46800					
square root = 216.33 km
the distance between them after 3 hours