### Home > CC4 > Chapter 2 > Lesson 2.2.2 > Problem 2-66

2-66.

Greta is opening a savings account. She starts with $100 and plans to add $50 each week. What is the unit rate of change for this situation? Write an equation Greta can use to calculate the amount of money she will have after any number of weeks. How much money will she have after 1 year? Homework Help ✎

*x* is the number of weeks starting with week 1, and *y* is the amount of money.

The *y*-intercept, or *b*, is the original (starting) price. The slope is the growth rate.

Both of these are given in the problem.

Substitute them into the equation.

There are 52 weeks in a year.

Remember that *x* is the week number.