Let
x--------> the number of weeks
f(x)------->Peter's total video game time in hours
we know that

The domain of the function is the interval [0, 8]
The y-intercept of the function is the point (0,10)
is the initial amount of hours Peter's played
The slope of the function is equal to

Is the rate at how many hours he is playing extra each week
using a graph tool
see the attached figure