[See the attached picture for better Understanding]
Answer:
After walking 40 yards in opposite directions and then 30 yards to left, Creek and Cold are now standing at the edges of tow triangles and the distance between them is the hypotenuse of two triangles with same measurments. So by using pythagoras theorem we can state that,
Distance between both of them is 100 yards.
See the attached picture.
Step-by-step explanation: