Hi there,
The equation to this is going to be : c = 3r - 3s
If you want to get the lower price down you are going to have to buy 3 shampoo bottles in order to get a lower price. The cost you save is the main difference from a regular price. And the answer is c = 3r - 3s
The total cost of the meal will be $17.64.
Slope= (Y2-Y1)/(X2-X1)
Slope=(3-(-4) ) /(-14-(-7) )
Slope= (3+4)/(-14+7)
Slope=7/-7
Slope= -1
Y=2x +4 is non proportional because b does not equal 0
The b in the equation is 4
As long as the y intercept is not more or less than 0, than it will be proportional