Question

PLS HELP ASAP!! WILL MARK BRAINLYIST
the value of a textbook is $63 and decreases at a rate of 11% per year for 13 years.
the exponential function that models the situation is y=?
after 13 years, the value of the textbooks is $?

Answer 1

Answer:

$13.85

Step-by-step explanation:

If the textbook decreases by 11% per year, this means it will be 89% of the previous year's value since 100% - 11% = 89%

89% in decimal form = 89/100 = 0.89

Therefore, the exponential function is:

$y = 63 \cdot 0.89^x$, where $x$ is the number of years

So when $x=13$,  

$y = 63 \cdot 0.89^{13}=13.84875..=13.85$