Is y=7x a discrete or continuous graph?

Question

Please help! The origional problem was: "Coal used for barbecues are sold in 7 lbs. Sketch a graph to show the weight of the coal purchased by a customer who buys 0, 1, 2, 3, or 4 bags. Tell whether the graph is continuous or discrete."

HELP ASAP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Answer 1

in the reel werld, yu gotta bi bags, & that gotta be positiv nonzero integers...1, 2, 3...

but as a math-man, yu kan model it & akt like its a equashun=strate line

all a mater av how yu look at it

Answer 2

This is a discrete graph because you cannot purchase a partial bag of charcoal. Your values would all be whole numbers (0 bags, 0 lbs) (1 bag, 7 lbs); (2 bags, 14 lbs); (3bags, 21 lbs); (4 bags, 28 lbs).

This is also an example of:

1. a function (passes the vertical line test)
2. direct variation because it runs thru (0,0)
3. x and y intercepts are both 0 and represent 0 bags(x) weigh 0 lbs (y)
4. bags (x) is the independent variable
5. lbs (y) is the dependent variable (the number of lbs DEPENDS on how many bags you purchase)
6. Inputs are bags
7. Outputs are lbs
8. Domain is {0, 1, 2, 3, 4} X values
9. Range is {0, 7, 14, 21, 28} Y values