To evaluate a function at a given input, you have to substitute every occurrence of the variable with that particular value.
So, for the first function, you have
The name of the variable is obviously irrelelvant, so the same goes for the second function:
Answer:
You have to invest $6,250
Step-by-step explanation:
very simple applying the simple interest formula which is
Given data
A, final amount = $10,000
P, initial principal balance= ?
r, annual interest rate = 7.5%
t, time (in years)= 8 years
we can substitute our given data to find the principal needed.
Divide both sides by 1.6 we have
P= $6,250