The total cost c for p pounds of salami if each pound costs $4.59

x:       y:  

-1         4

0         4

1         6

2         18

3         20  

step-by-step explanation:

assume that y=mx+n

you may see as , where

in we change places of numerator and denominator, then we insert an opposite sign

and substitute m=-1/3 in the equation y=mx+n

point (4,2), so we substitute x=4, y=2 to the equation and calculate

the answer is