Answer:
f(x) = 0.85x
g(x) = 0.85x - 100
Step-by-step explanation:
Given that :
Sale price = 15% off the item price
Let original price = x
Hence, sale price = (100 - 15)%
Let the sale price function = f(x)
f(x) = 0.85x
Where, x = price before 15% off
Customer also has a coupon discount of 100 pesos
Let coupon discount price = g(x)
g(x) = f(x) - 100
Hence,
g(x) = 0.85x - 100
x = price before 15% off
