The line graph shows the cost of inflation in some country. What cost $10,000 in 1975 would cost the amount shown by the graph in subsequent years. Below are two mathematical models for the
lata shown in the graph. In each formula, C represents the cost x years after 1980 of what cost $10,000 in 1975.
Model 1 C = 840x +15,538
Model 2 C= -222 +900x + 14,204