Question 154109
Avoiding a collision. A car is traveling on a road that is perpendicular to a railroad track. When the car is 30 meters from the crossing, the car's new collision detector warns the driver that there is a train 50 meters from the car and heading toward the same crossing. How far is the train from the crossing? 
-----------
Draw the picture.
It is a right triangle with the car 30 meters from the 90 degree vertex
and the train 50 meters (along the hypotenuse) from the car.
You want to find the 3rd side of the triangle which is the distance
the train is from the vertex of the 90 degree angle.
---------------
Use Pythagoras:
50^2 = x^2 + 30^2
x^2 = 2500-900
x = sqrt(2600)
x = 50.99.. meters
That is the distance the front of the train is from the center
of the intersection.
===============
Cheers,
Stan H.