In JS solution :
Test case does not meet description : speedError(8,2,[[5,1.82 ],[5,0.48]])

Value 8 is bigger then ~5.
Making radar position not perpendicular to road.

Tested some aprooved solutions and this breaks pythagorean calculations.
Math.sqrt(55 - 88) => NaN.

I liked this kata but need some improvements.

Testing functions should not be put in Preloaded. They belong in the actual tests.

Node 8+ should be enabled.

The description is really unclear. I read the description many times and still has no idea what you meant by

estimate of the distance between the officer and a point on the road (specifically, the point at which the car will be travelling perpendicular to the estimated distance)

Or what that point is. You really need to put up a diagram or something.

Sample test:

// Test that negative input for distance in readings array throws error
Test.expectError("One of the distances in readings array was negative", function() { 
  speedError(6,3,[[-50,0],[30,1]]);
  });
// Test that a 0 input for distance in readings array throws error
Test.expectError("One of the distances in readings array was negative", function() { 
  speedError(6,3,[[0,0],[-30,1]]);
  });

The second test does not actually test what is intended to be tested because it's shadowed by the condition in the first test (there's a -30 here).

Hi danmarcus. Check this test:

distance estimate  actual distance             readings
        7               5              [ [ 1, 0.71 ], [ 46, 1.35 ] ]

Is it possible that the reading of the distance from the radar gun to the car be less than the cop from the road?