Выполни задания

Представь в виде дроби выражение.

1. \(\dfrac{9}{10mn}-\dfrac{14}{15mn}=\) [ \(-\frac {1}{30mn}\) | \(\frac {1}{mn}\) | \(mn\) | \(\frac {m}{n}\) ];
2. \(\dfrac{2x^2-4y^2}{xy}+\dfrac{6x+4y}{x}=\) [ \(\frac {2(x+3y)}{y}\) | \(\frac {y}{x+3y}\) | \(\frac{x-3y}{x+3y}\) | \(\frac {1}{x-3y}\) ];
3. \(7-\dfrac{5x+7y}{y}=\) [ \(-\frac {1}{xy}\) | \(\frac yx\) | \(-\frac {5x}{y}\) | \(\frac xy\) ];
4. \(\dfrac{x^2-y^2}{4x+y}+4x-y=\) [ \(\frac{17x}{4x+y}\) | \(\frac {1}{4x+y}\) | \(\frac{17x^2-2y^2}{4x+y}\) | \( \frac{17x^2}{4x+y}\) ].