Question 1161644
x, how many units
C, cost of those x units
points (x,C)


(10,40) and (20,70) and you want the point on the line, find the unknown coordinate in (35,C).


{{{C-40=((70-40)/(20-10))(10-35)}}}------this is based on point-slope form equation of a line.  Simplify and solve for C.