mml=<math xmlns="http://www.w3.org/1998/Math/MathML"><mfrac><mi mathvariant="normal">x</mi><mi mathvariant="normal">y</mi></mfrac><mo>-</mo><mfrac><mi mathvariant="normal">x</mi><mrow><mi mathvariant="normal">x</mi><mo>+</mo><mn>10</mn></mrow></mfrac><mo>=</mo><mn>1</mn><mspace linebreak="newline"/><mo>&#x21D2;</mo><mi mathvariant="normal">x</mi><mfenced open="[" close="]" separators="|"><mfrac><mrow><mfenced separators="|"><mrow><mi mathvariant="normal">y</mi><mo>+</mo><mn>10</mn></mrow></mfenced><mo>-</mo><mi mathvariant="normal">y</mi></mrow><mrow><mi mathvariant="normal">y</mi><mfenced separators="|"><mrow><mi mathvariant="normal">y</mi><mo>+</mo><mn>10</mn></mrow></mfenced></mrow></mfrac></mfenced><mo>=</mo><mn>1</mn></math>