To evaluate the statements regarding the polynomial equation \( y = x^4 + 3x^3 - x^2 - 3x \):
1. **Statement #1**: The equation has four non-real solutions because there are four x-intercepts.
- This statement is false. The presence of x-intercepts indicates that there are real solutions. Therefore, if there are four x-intercepts, the solutions are real, not non-real.
2. **Statement #2**: The equation has three real solutions because there are three turning points on the graph.
- This statement is also false. The number of turning points (local maxima and minima) in a polynomial graph is typically less than or equal to the degree of the polynomial minus one. A quartic polynomial such as this one may have up to three turning points but can have four real roots (solutions).
3. **Statement #3**: The equation has four real solutions because there are four x-intercepts.
- This statement is true. If the graph crosses the x-axis at four distinct points, it means that the polynomial has four real solutions corresponding to those x-intercepts.
Based on this reasoning, **Statement #3 is true**.