Question 563509
p = mx + b
If the p=75, then x=10:
75 = 10m + b [1]
If p=40, then x=45:
40 = 45m + b [2]
Subtract [2] from [1]:
35 = -35m
m = -1
Use one of the two equations above to solve for b:
75 = -10 + b
b = 85
So the equation is p = -x + 85