АЛГЕБРА 8 КЛАСС, ПОМОГИТЕ РЕШИТЬ. ДАЮ 30 БАЛЛОВ. С.Р. 8 НОМЕРА С 1 ПО 4

N1
$1) \frac{28 - 39}{36xy} = - \frac{11}{36xy}$
$2) \frac{2xy - 5 {x}^{2} + 6 {y}^{2} + 5 {x}^{2} }{xy} = \frac{2(x +3 y)}{x}$
$3) - \frac {3x}{y}$
$4) \frac{ {x}^{2} - {y}^{2} + {x}^{2} - 3 {y}^{2} }{x + 3y} = - \frac{4 {y}^{2} }{x + 3y}$
N2
$1) \frac{4x}{3(x - 7)} - \frac{3x}{2(x - 7)} = \frac{8x - 9x}{6(x - 7)} - \frac{x}{6(x - 7)}$
$2)\frac{3x}{3x + 2y} - \frac{9 {x}^{2} }{( {3x + 2y)}^{2} } = \frac{ {9x}^{2} + 6xy - 9 {x}^{2} }{( {3x + 2y)}^{2} } = \frac{6xy}{( {3x + 2y)}^{2} }$
$3) \frac{4x - 2x - 12}{x( {x}^{2} - 36) } = \frac{ 2}{ {x}^{2} - 36}$
N3