The amount a hardware store pays for buying nylon rope is represented by the equation y 5 0.12x, where y is the price it pays for x feet of rope. The amount the hardware store charges when selling the rope is represented by the graph.
The profit the store makes on the rope can be found by subtracting the amount it charges for the rope from the price it pays for the rope. If the store sells 80 feet of rope, how much profit does it make on that rope?
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Please answer I really need help.