Question 564723
they are travelling at right angles to each other.							
At any given instant they form a right triangle with their starting point							
							
speed of one = x			South bound				
 other speed = x+3			East bound	

after two hours 
they will be 2x & 2(x+3) miles away from the starting point

(2x)^2+(2(x+3))^2=900
4x^2+(2x+6)^2=900

4x^2+4x^2+24x+36=900

8x^2+24x-864=0
/8
x^2+3x-108=0
x^2+12x-9x-108=0
x(x+12)-9(x+12)=0
(x+12)(x-9)=0
take the postive value
x= 9 mph the speed of south bound
12mph east bound