Answer:
a. y = 0.15x + 20
b. the slope (0.15) represents how much the energy company charges per hour.
c. the y-intercept (20) represents the connection fee that you pay starting out.
d. the independent variable is the y-intercept (20) because it only relys on itself
e. the dependent variable is the slope (0.15) it relys on the x variable and the y-intercept (20).
f. 21 hours of usage will cost $23.15 + 20
so the final cost for 21 hours of usage will be $43.15.