6. positive linear
7. both calculated the slope as 2/3
8. slope = (145 - 190) / (1 - 0) = -45....rate of change(slope) = -45 per month
10. (0,60)(1,90)...slope = (90 - 60) / (1 - 0) = 30
y = mx + b
slope(m) = 30
(0,60)...x = 0 and y = 60
60 = 30(0) + b
60 = b
equation is : y = 30x + 60...fixed amount is 60
