Answer:
[tex]\frac{7}{9}[/tex]
Step-by-step explanation:
[tex]1-\frac{4}{2\cdot \:7+4}\\\\\frac{4}{2\cdot \:7+4} = \frac{2}{9} \\\\=1-\frac{2}{9}\\\\\mathrm{Convert\:element\:to\:fraction}:\quad \:1=\frac{1\cdot\:9}{9}\\\\=\frac{1\cdot \:9}{9}-\frac{2}{9}\\\\Since\:the\:denominators\:are\:equal,\\\:combine\:the\:fractions}:\\\\\quad \frac{a}{c}\pm \frac{b}{c}=\frac{a\pm \:b}{c}\\\\=\frac{1\cdot \:9-2}{9}\\\\1\cdot \:9-2 =7\\\\=\frac{7}{9}[/tex]
