Question

when justin left his house this morning, his cell phone was 50% charged and it then started to lose 5% charge for each hour thereafter. write an equation for b, in terms of t, representing the charge remaining in justins battery, as a percentage, t hours after justin left his house.

number of hours since justin left his house	percentage charge remaining on phone battery

|0|
|1|
|2|
|3|

answer attempt 1 out of 2

you must answer all questions above in order to submit.

Explanation:

Step1: Identify the initial value

The initial charge is 50%, so when $t = 0$, $B=50$.

Step2: Determine the rate of change

The battery loses 5% charge per hour. So the change in charge per hour is - 5.

Step3: Write the linear - equation formula

The general form of a linear equation is $y=mx + b$, where $m$ is the slope and $b$ is the y - intercept. In our case, $B$ is the dependent variable (percentage of charge remaining), $t$ is the independent variable (number of hours), $m=-5$ and $b = 50$. So the equation is $B=50-5t$.

Answer:

$B = 50-5t$