I don't have an answer for you, but I do have an important hint ... one that will stand you in good stead as you go further in your mathematical studies:
The reason there's a drawing right next to this question in the book or on the homework sheet is that the question can't be answered without the drawing.
The coordinates of point C can vary depending on the conditions specified. If we are finding the midpoint of points A(-2, -8) and B(1, 1), the coordinates of C would be (-0.5, -3.5). Always refer to diagrams or additional instructions for the correct interpretation.
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