4x/9 + 2 = 2/3 | * 9
4x + 18 = 2*3
4x + 18 = 6
4x = 6 - 18
4x = - 12
x = - 12 : 4
х = - 3
проверим:
(4* (-3)) /9 + 2 = - 4/3 + 2 = 2 - 1ц. 1/3 = 2/3
(6х - 91)/7 = - 19
6х - 91 = - 19 * 7
6х - 91 = - 133
6х = - 133 + 91
6х = -42
х = - 42 : 6
х = - 7
проверим:
(6 *(-7) - 91)/ 7 = (-42-91)/7 = -133/7 = - 19
6х/7 + 3 = 3/7 | *7
6x + 21 = 3
6x = 3 - 21
6x= -18
x= -18 : 6
х = - 3
проверим:
(6 * (-3) )/7 + 3 = -18/7 + 3 = 3 - 2 ц. 4/7 = 3/7