Question

A brand new smartphone costs $1200. It decreases in value by 13. 3% every year after its purchase. Which function models the value of the phone x years after its purchase?


Question 8 options:


f(x)=1. 133(1200)x


f(x)=1200(1. 133)x


f(x)=1200(0. 867)x


f(x)=0. 867(1200)x

Answer 1

The function that models the value of the phone x years after its purchase is y = 1200(0.867)^x

Exponential equations

The standard exponential equation is given as:

y = ab^x

From the given question

a = 1200

b = 1 - 0.133

x is the time

Substitute to have:

y = 1200(1-0.133)^x
y = 1200(0.867)^x

Hence the function that models the value of the phone x years after its purchase is y = 1200(0.867)^x

Learn more on exponential equation here: https://brainly.com/question/2456547