We can calculate the rate of change between two points (x1,y1) and (x2,y2) as:
As function is linear, the rate of change will be constant for all points.
We choose points (-5,7) and (-3,1) and calculate the rate of change:
Then, the rate of change has a value of -3.
Now, we have to find the initial value.
We interpret that the initial valule of a function is the value of y when x=0.
To find that, we need to use the equation of the line.
Knowing the slope (m=-3) and one of the points, like (-5,7), we can write the slope-point form of the equation:
We then can find y(0) replacing x with 0:
The initial value y(0) is y=-8
Answer:
2) -3 [Option B]
3) -8 [Option A]