You start out with $20 and then spend money in a store where every item is $3. Y = -3x + 20. Using the graph you drew for the equation, predict the amount you will have left if you buy 4 items.

Question

ash2326 · Answer

$$Y=-3x+20$$
Y is the amount left when we make x purchases
if we we purchase 4 items, x=4
$$Y=-3 \times 4+20=-12+20=$8$$
We can also find this from the graph
Let's plot the graph
Put x=0, we get y=20 ---> so one point is (0, 20)
Put y=20 we get x= 20/3 ---> (20/3, 0)
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