51cf3910-86bd-4cea-b4c4-bcd13ef8ae6d.html

<h3>Cool Down 5 min</h3>
<h4>Student Activity</h4>
<p>For each expression, write an equivalent expression in standard form. Show your reasoning.</p>
<ol class="os-raise-noindent">
  <li>\((2x+5)(x+1)\)</li>
</ol>
<p>Write down your answer, then select the <strong>solution</strong> button to compare your work.</p>
<p><strong>Answer:</strong> \(2x^2+7x+5\). The diagram shows that\((2x+5)(x+1)=2x \cdot x+2x \cdot 1+5 \cdot x+5 \cdot
  1\). Adding this together gives \(2x^2+7x+5\) in standard form.</p>
<br>
<table class="os-raise-doubleheadertable">
  <thead>
    <tr>
      <th scope="col"></th>
      <th scope="col">\(2x\)</th>
      <th scope="col">\(5\)</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <th scope="row">\(x\)</th>
      <td>\(2x^2\)</td>
      <td>\(5x\)</td>
    </tr>
    <tr>
      <th scope="row">\(1\)</th>
      <td>\(2x\)</td>
      <td>\(5\)</td>
    </tr>
  </tbody>
</table>
<br>
<ol class="os-raise-noindent" start="2">
  <li>\((x-2)(x+2)\)</li>
</ol>
<p>Write down your answer, then select the <strong>solution</strong> button to compare your work.</p>
<p><strong>Answer:</strong> \(x^2-4\). \((x+2)(x-2)=x^2+(-2x)+2x+(-4)=x^2-4\). The diagram also shows that
  \((x+2)(x-2)=x^2-4\).</p>
<table class="os-raise-doubleheadertable">
  <thead>
    <tr>
      <th scope="col"></th>
      <th scope="col">\(x\)</th>
      <th scope="col">\(2\)</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <th scope="row">\(x\)</th>
      <td>\(x^2\)</td>
      <td>\(2x\)</td>
    </tr>
    <tr>
      <th scope="row">\(-2\)</th>
      <td>\(-2x\)</td>
      <td>\(-4\)</td>
    </tr>
  </tbody>
</table>