Question

Do number 8 please.Assuming that the formula is valid for previous times, what was the car worth one year ago?

Answer 1

Since the value in dollars x years from now is given by:

`12,000((9)/(10))^x^{}`

And the moment "right now" can be represented as x=0, then replace 0 for x in the expression and evaluate it. Since every number elevated to the 0th power is equal to 1, then:

`12,000((9)/(10))^0=12,000(1)=12,000`

Therefore, the car is worth $12,000 right now.

To find the value of the car one year ago, notice that the time "one year ago" can be represented with x=-1. Then, replace x=-1 into the formula:

`12,000((9)/(10))^(-1)=12,000((10)/(9))=13,333.33\ldots`

Therefore, the car was worth approximately $13,333.33 one year ago.