Example of MathML embedded in an XHTML file

Given the quadratic equation $a<!--\; \; -->x^2+b<!--\; \; -->x+c$ , the roots are given by $x=\frac{-<!--\; -\; -->b\pm <!--\; \pm \; -->\sqrt{b^2-<!--\; -\; -->4<!--\; \; -->a<!--\; \; -->c}}{2<!--\; \; -->a}$ .