Answer:
21
Step-by-step explanation:
average 9 pounds per three weeks
divide 9 in 3 three weeks
3 pounds per week
7 times 3 is 21
Y = mx + b
slope(m) = 3/4
(5,-4)...x = 5 and y = -4
now we sub
-4 = 3/4(5) + b
-4 = 15/4 + b
-4 - 15/4 = b
-16/4 - 15/4 = b
- 31/4 = b....or - 7 3/4 = b
so ur equation is : y = 3/4x + (-31/4) or y = 3/4x - 31/4