### Home > CAAC > Chapter 4 > Lesson 4.2.4 > Problem 4-100

The table below shows the amount of money Francis had in his bank account each day since he started his new job. 4-100 HW eTool (Desmos). Homework Help ✎

Days at New Job

Money in Account

0

$27

1

$70

2

$113

3

$156

Write a rule for the amount of money in Francis's account. Let

*x*represent the number of days and*y*represent the number of dollars in the account.When will Francis have more than $1000 in his account?

What was Francis' starting point, or *b*?

What is the growth each month, or *m*?

Substitute these values into the equation *y* = *mx* + b.

Which variable represents the amount of money?

Substitute $1000 for this variable in your rule.

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