Answer:
1.
Clean machine slope: 3/2
Sudz slope: 3/2
This means they rise and run at the same rate.
2.
y intercept of clean machine: 2
y intercept of sudz: 4
this tells us that the cost for sudz is higher per pound.
3.
Clean machine because 4 pounds at sudz costs 10 dollars, while 5.5 pounds at clean machine costs 10 dollars. You get more for less at clean machine.
4.
a. plot these points
Brand A: (0,100) (1,150)
Brand B: (0,200) (1,225)
b. Brand B cuz 25 is lower than 50