x - 3/x + 7/x + 3 = 5/4(( x - 3)(x + 3) + 7x) / x(x+ 3) = 5/4( x² - 9 + 7x) / x( x + 3) = 5/44( x² + 7x - 9) = 5x( x + 3)4x² + 28x - 36 = 5x² + 15x4x² - 5x² + 28x - 15x - 36 = 0- x² + 13x - 36 = 0x² - 13x + 36 = 0D = b² - 4ac = 169 - 4×36 = 169 - 144 = 25 = 5²x1 = ( 13 + 5) / 2 = 9x2 = ( 13 - 5) / 2 = 4Ответ: x1 = 9, x2 = 4.