The initial budget equation for pop (p) and movies (m) is Qp = 20 - 4Qm, and the price of a movie is $20. If the price of a movie falls to $15, what is the new budget equation?
A) Qp = 15 - 11Qm
B) Qp = 20 - 15Qm
C) Qp = 15 - 4Qm
D) Qp = 20 - 3Qm
E) Qp = 25 - 5Qm
can you explain the equations and the steps to solve it