Answer:
13
Step-by-step explanation:
Since a point on the line is (0, 13) we know that the y-intercept is 13. The answer is already written in slope-intercept form so the answer is 13.
Let the missing value be c.
y = -3x + c
Put x as 0, and y as 13.
13 = -3(0) + c
13 = 0 + c
13 = c
