Question 380439
Here is something to just put in your memory for ever.
This is a clasic 3, 4, 5 triangle.
The train is 40 meters away from the intersection.
Use c^2=a^2+b^2 to calculate.
50^2=30^2+b^2
2500=900+b^2
1600=b^2
sqrt 1600=40 meters