title: Plots not showing up in R html document
body: <p>I've written some simple code to plot some data, but for some reason I can't get it to print out on the html document when I knit it?</p>
  
  <pre class="lang-r prettyprint-override"><code>library(datasets)
  library(ggplot2)
  ggplot(ChickWeight, aes(x = Time, y = weight)) + geom_point()
  </code></pre>
  
  <p>I expect to see an image in the output, but instead, I just see the html code for one...</p>
  
  <pre><code>'''r
  library(datasets)
  library(ggplot2)
  ggplot(ChickWeight, aes(x = Time, y = weight)) + geom_point()
  '''
  
  &lt;img src="hw5_files/figure-html/unnamed-chunk-3-1.png" width="672" /&gt;
  </code></pre>
  
  <p>Is there any reason why this would be happening? I'm using Ubuntu 18.04 and R 3.4.4</p>
  
  <h2>Edit:</h2>
  
  <p>My entire markdown file for this looks like this:</p>
  
  <pre><code>---
  title: DS Homework
  author: Aaron
  date: 4/10/2020
  output: html_document
  ---
  
  1. Question 1:
    a. Some part a
    b. Some part b
  
      '''{r}
      library(datasets)
      library(ggplot2)
      ggplot(ChickWeight, aes(x = Time, y = weight)) + geom_point()
      '''
  2. Question 2:
  </code></pre>