To answer your question accurately, I would need more details about "problem 13" and the context of the problem, as well as the specific function or curve involved. Typically, the equation of a tangent line to a curve is unique at any given point, but certain problems may involve more complex curves or scenarios where multiple tangents can be drawn.

If the curve is a standard one (such as a polynomial, trigonometric function, etc.), a tangent line at a specific point is generally unique. However, if the problem involves:

• Implicit functions, which can sometimes yield multiple tangents at a given point.
• Parametric equations, which might allow multiple tangents at different parameter values corresponding to the same point.
• Curves with cusps or vertical tangents, which could also lead to the existence of more than one tangent at specific locations.

Feel free to upload the problem or describe it in more detail, and I can give you a more precise answer.

Would you like me to elaborate on this or explore specific scenarios?
Here are five questions to expand on the idea:

1. What type of function is involved in the problem?
2. Is the tangent line supposed to be at a specific point on the curve?
3. Are you dealing with implicit differentiation or parametric equations?
4. Does the curve have any critical points, such as cusps or vertical tangents?
5. Could the problem involve symmetry where multiple tangents might occur?

Tip: When finding tangent lines, always remember that the slope of the tangent is given by the derivative of the function at the point of tangency.