Answer:
y = 3
Explanation:
Equation of a line: y = mx + b
Substitute -1/7 for m, slope AND x and y for point (5,1).
1 = (-1/7)(5) + b
Simplify and Isolate b
1 = (-5/7) + b
b = 1 + 5/7
b = 12/7
Sub b=12/7 and m=-1/7 for equation of a line.
y = -1/7 x + 12/7
Sub x = -9 to find the missing y coordinate.
y = (-1/7)(-9) + 12/7
y = 21/7
y = 3
The point is (-9, 3).