answer: hence, function will be
![y=85(\frac{3}{4})^x](/tex.php?f=y=85(\frac{3}{4})^x)
explanation:
since we have given that
cost of a new textbook = $85
according to question, the resale value of a textbook decreases by 25% with each previous owner,
so, our function becomes,
![y=85(1-\frac{25}{100})^x\\\\y=85(\frac{100-25}{100})^x\\\\y=85(\frac{75}{100})^x\\\\y=85(\frac{3}{4})^x](/tex.php?f=y=85(1-\frac{25}{100})^x\\\\y=85(\frac{100-25}{100})^x\\\\y=85(\frac{75}{100})^x\\\\y=85(\frac{3}{4})^x)
here, y is the total value of the text book after x owners.
hence, function will be
![y=85(\frac{3}{4})^x](/tex.php?f=y=85(\frac{3}{4})^x)