Answer:
r = -19
Explanation:
To find the value of r, we can use the slope formula and the two given points:
slope = (y2 - y1) / (x2 - x1)
where (x1, y1) = (3, r) and (x2, y2) = (1, -7).
Substituting these values, we get:
6 = (-7 - r) / (1 - 3)
Simplifying and solving for r, we get:
6 = (-7 - r) / (-2)
Multiplying both sides by -2, we get:
-12 = 7 + r
Subtracting 7 from both sides, we get:
r = -19
Therefore, the value of r is -19.