A town's population has been growing linearly. In 2003, the population was 40000, and the population has been growing by 2200 people each year.

Question

A town's population has been growing linearly. In 2003, the population was 40000, and the population has been growing by 2200 people each year.

Write an equation for the population xx years after 2003.

Answer 1

y = mx + b where m is our slope or rate of change and b is our y-intercept (where x = 0).

Since 2003 is year 0 (2004 is year 1, right?), b = 40,000

If it's growing by 2200 per year, m = 2200

y = 2200x + 40,000

So, what's the population going to be in 2023? That's 20 years later.

y = 2200(20) + 40,000

Hope this helps!