I assume by starting value, you mean y-intercept. The y-intercept is 15
To find this, we need to use slope intercept form and the given information to find it.
y = mx + b ----> plug in the known values
9 = -3/4(8) + b
9 = -6 + b
15 = b
Therefore, the starting value is 15.
I believe b is about 16.3, hope this helps
Answer:

Step-by-step explanation:

Answer:
b) 1000x + 115
Step-by-step explanation:
C = 20y + 15
= 20(50x + 5) + 15
= 1000x + 100 + 15
= 1000x + 115