We can use Triangle Inequality Theorem, the length of the third side of a triangle must always be between (but not equal to) the sum and the difference of the other two sides.
4.1 - 1.3 < x < 4.1 + 1.3
2.8 < x < 5.7
so, the answer is 2.8 < x < 5.7
Andy is incorrect because more then one triangle can be drawn with the given information
