Set Up MathJax

Include this text somewhere in your document. MathJax recommends to placing it in the HTML header, but it may also appear in the body of the document.

<script type="text/javascript" async 
  src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/latest.js?config=TeX-MML-AM_CHTML">
</script>

For comprehensive documentation see the MathJax website

AsciiMath

In the Markdown text you need to escape the backticks, unless they are enclosed in HTML tags, for example to center a display equation.

When \`a != 0\`, there are two solutions to \`ax^2 + bx + c = 0\`. 
They are:

<p style="text-align:center">
  `x = (-b +- sqrt(b^2-4ac))/(2a) .`
</p>

Output:

When `a != 0`, there are two solutions to `ax^2 + bx + c = 0`. They are:

`x = (-b +- sqrt(b^2-4ac))/(2a) .`