M = (y2 - y1) / (x2 - x1)
1/4 = (5-3) / (r +4)
1/4 = 2/ (r + 4)
Cross multiply
2*4 = r + 4
8 = r + 4
Subtract 4 from both sides
4 = r
CHECK
(-4,3)(4,5)
m = (5-3)/(4--4) = 2/8 = 1/4
That would be 8 subscribers and they would earn 78
I'm not for sure but I think it's ten
Is will be 300 rounded to the nearest 100 :)