In order to create text that contains a LaTeX formula as well as text you may enter the text inside text while LaTex Formula is activated. Each equation should be write in-between begin equation and end equation tags. The font type LaTeX uses in math mode is somewhat special since it is optimized for writing mathematical formulas.
Yet there is an alternative that offers a little more flexibility.
Text The length of the diagonal is sqrt 2 Note. The colour of a second block of text delimited by and is set to red with the command colorred then a 05mm-thick horizontal ruler is inserted by rulelinewidth05mm. As you see the way the equations are displayed depends on the delimiter in this case and. By default Latex will print text within formulas in italics omitting white spaces.