Answer:
y - 5 = -1(x - 3)
Explanation:
Moving from the point (3, 5) to the point (7, 1), we see that the run (x) increases by 4 and the rise (y) decreases by 4. Hence, the slope of the line connecting these two points is m = rise / run = -4/4 = -1.
Then the point-slope form of the equation of this line is found from
y - k = m(x - h), or specifically:
y - 5 = -1(x - 3)