1. Solution: Let each A car have x seats, then each B car has (x+5) seats.

Because a batch of rented cars of type A are just full, there are 240/x cars of type A and [(240/x)-2 cars of type B,

(x+5)[(240/x)-2]- 10=240

solve

X 1=-30 (truncated)

x2=20

x+5=25

So each model A has 20 seats and each model B has 25 seats.

2. Solution: Obtained from the equation. In the two solutions, x 1=y2, x2=y 1, namely a 1=b2, a2=y 1,

Therefore, the value of a 1a2-b 1b2 is 0.