5a: To find the slope, you would divide the difference of the y-coordinates of 2 points on a line by the difference of the x-coordinates of those same 2 points. So coordinates (15,1.5) and (5,0.5). You would subtract 1.5 form 0.5 which gives you neagtive one. (-1) Then subtract 15 from 5 which is -10. (negative ten) -1 divided by -10 is one tenths. 1/10 is your answer to part a.
5b. To find the slope, you would divide the difference of the y-coordinates of 2 points on a line by the difference of the x-coordinates of those same 2 points. (Not sure what you meant by "interpret".
5c. The phone bill will increase by $0.50 if you talk for 5 extra minutes.
5d. You talked for 30 minutes if the phone bill costs $3.
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6a. I can't really graph it but I'll interpret the slope. Y would basically be 7.5 times as much as x.
6b. I'm kinda stuck on how to get from 7.5 to 1. Sorry. OnO
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7a. Hamburgers sell faster because there are 60 minutes in a hour. If 2.5 wraps are sold in one minute. Then there would be 150 wraps sold in 60 minutes which is also one hour. Hamburgers sell ten more than wraps per hour.
7b. The equation for wraps is: y=2.5x
The equation for hamburgers is y=2.6667x
Goodnight and hope it helps.~ RIP my sleep...