-2/3
Пошаговое объяснение:
3/4(1/2х + 2/3) = 3х + 2 1/4
3/8х + 6/12 = 3х + 2 1/4
3/8х - 3х = 2 1/4 - 6/12
3/8х - 2 8/8х = 2 3/12 - 6/12
-2 5/8х = 27/12 - 6/12
-21/8х = 21/12
х = 21/12 : (-21/8)
х = 21/12 * (-8/21)
х = 1/3 * (-2/1)
х = -2/3
