Question

Using the table below, write a function rule for the balance in the CD account after any number of years. Let y represent the value of the investment at the end of any year x.

CD/Year
Beginning Balance
Interest Earned
Ending Balance
Savings Account/Year
Beginning Balance
Interest Earned
Ending Balance
1
$700
$22
$722
1
$700
$25.90
$725.90
2
$722
$22
$744
2
$725.90
$26.86
$752.76
3
$744
$22
$766
3
$752.76
$27.85
$780.61
4
$766
$22
$788
4
$780.61
$28.88
$809.49
5
$788
$22
$810
5
$809.49
$29.95
$839.44

Answer 1

y = 700 +22x

Explanation:

The CD account balance is 722 after the first year and increases by $22 each year. The function rule is a linear function with a y-intercept of 700 and a slope of $22 per year.

y = 700 +22x . . . . . . ending balance after x years