Whats the question? its not there
You never gave the speed of the blue train.
The path to collision is equal to 1½ circles.
1.5 x 210 meters
= 315 meters
I'm going to arbitrarily guess the speed of the blue train is 15 meters per minute. They are therefore approaching each other at a combined rate of 35 meters per minute.
315 / 35 = 9 minutes
Answer:
9 minutes
Well you're gonna wanna start at -13 for the y intercept, and then go 3 up every x, just like the equation y = 3x +13.