To find the midpoint \( M \) of a line segment with endpoints \( R(x_1, y_1) \) and \( S(x_2, y_2) \), you can use the midpoint formula:
\[ M \left( \frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2} \right) \]
Given the coordinates of the endpoints \( R(5, 7) \) and \( S(1, 5) \):
- \( x_1 = 5 \)
- \( y_1 = 7 \)
- \( x_2 = 1 \)
- \( y_2 = 5 \)
Now plug these values into the formula:
\[ M \left( \frac{5 + 1}{2}, \frac{7 + 5}{2} \right) = M \left( \frac{6}{2}, \frac{12}{2} \right) = M(3, 6) \]
Therefore, the coordinates of the midpoint \( M \) are:
\[ M = (3, 6) \]