4dbe1dd7-693e-49b0-9379-e14c50b59ec6.html

<p>For questions 1-2 , use the following prompt and image.</p>

<blockquote> The image shows the battery usage of a cell phone 9 hours after it was fully charged. It also shows a prediction that the battery would last 8 more hours.</blockquote>

<p><img src="https://k12.openstax.org/contents/raise/resources/878a59b47b031b568820dd2669e635e32855b6a1" alt="graph of battery usage" width="300"/></p>
<ol  class="os-raise-noindent">
  <li> Write an equation for a model that fits the data in the image and gives the percent of battery power as a function of time since the phone was fully charged. Be prepared to show your reasoning.
</li>
</ol>
<ol  class="os-raise-noindent" start="2">
  <li> Based on your function, what percentage of power would the battery have 4 hours after this image was taken? What about 5 hours after the image was taken? Be prepared to show your reasoning. </li>
</ol>

<p>For questions 3-5, use the following prompt and images.</p>
<blockquote>Here are two more images showing the battery usage at two later times, before the battery was charged again. </blockquote>
</ol>
<p><img src="https://k12.openstax.org/contents/raise/resources/e759b18e61a284924951bc44fec6d6c6471b4fe9" alt="Two images of advanced battery usage, 29 percent and 7 percent." width="550"/></p>
<ol class="os-raise-noindent" start="3">
  <li> How well did the function you wrote predict the battery power 4 and 5 hours after the first image was taken (that is, 13 and 14 hours after the battery was fully charged)? Be prepared to show your reasoning. </li> <br>
</ol>
<ol  class="os-raise-noindent" start="4">
  <li> What do you notice about the change in the prediction between \( t=13 \) and \( t=14 \)?</li> <br>
</ol>
<ol  class="os-raise-noindent" start="5">
  <li> Write a new equation for a function that would better fit the data shown in the last image. </li>
</ol>

<div class="os-raise-usermessage-lightbulb">
  <p>If you get stuck, consider creating a table of values or a scatter plot of the data. </p>
  </div>