We need to find out what percentage $912 is of $15 200. The answer is 6%, if I'm understanding the question correctly.
For this case we have the following functions:
h (x) = 2x - 5
t (x) = 6x + 4
Part A: (h + t) (x)
(h + t) (x) = h (x) + t (x)
(h + t) (x) = (2x - 5) + (6x + 4)
(h + t) (x) = 8x - 1
Part B: (h ⋅ t) (x)
(h ⋅ t) (x) = h (x) * t (x)
(h ⋅ t) (x) = (2x - 5) * (6x + 4)
(h ⋅ t) (x) = 12x ^ 2 + 8x - 30x - 20
(h ⋅ t) (x) = 12x ^ 2 - 22x - 20
Part C: h [t (x)]
h [t (x)] = 2 (6x + 4) - 5
h [t (x)] = 12x + 8 - 5
h [t (x)] = 12x + 3
Amount financed
320−100=220
Total paid
100+25×12=400
Interest paid
400−320=80
Interest rate=(2yc)÷(m (n+1))
I=(2×12×80)÷(220 (12+1))
I=(2×12×80)÷(220×13)
I=0.67×100
I=67%
