Answer:
y = 4000 - 70x
Linear function.
Step-by-step explanation:
Let x = number of weeks.
In 1 week, he withdraws $70.
That means -70 in 1 week.
After the second week, he will have withdrawn 2 times $70, or
-70 × 2
After 3 week, he will have withdrawn -70 × 3
After x weeks, he will have withdrawn $70 × x,or simply -70x.
He starts with 4000, so after x weeks, he has 4000 - 7x.
Let y = the amount of money at week x.
The equation is
y = 4000 - 70x
This is a linear function.
