Answer:
y= -45x + 380 based on how many pages are left or
y= 45x based on how much he read
Step-by-step explanation:
Anyways, lets solve with the first formula
1. A week is seven days, so substitute 7 as x.
y= -45(7)+380
-45 (7) = -45 x 7 = -315
-315+380= 65
He has 65 pages left after the week which means he has not finished the book
2. The Formula
Use the formula y=mx+b
m is the slope or the rate of change. What is affecting the constant number of 380?
The 45 pages he is reading change how many pages he has left right?
That means the 45 that is changing b is the slope or m, but it is negative because its affecting how many pages he has left in a negative way.
b is the starting value
That is 380 pages left, which is what he starts off as the slope
Hence the equation is
y=-45x+380
