77-(28+y) = 2777 - 28 - y = 2749 - y = 27-y = 27 - 49-y = -22y = 22
90 + y x 8 = 15490 + 8y = 1548y = 154 - 908y = 64y = 64 / 8y = 8
9x + 50 = 869x = 86 - 509x = 36x = 36 / 9x = 4
120:(x-19) = 6120 / (x - 19) = 6x - 19 = 120 / 6x - 19 = 20x = 20 + 19x = 39
77-(28+y) = 27
77 - 28 - y = 27
49 - y = 27
-y = 27 - 49
-y = -22
y = 22
90 + y x 8 = 154
90 + 8y = 154
8y = 154 - 90
8y = 64
y = 64 / 8
y = 8
9x + 50 = 86
9x = 86 - 50
9x = 36
x = 36 / 9
x = 4
120:(x-19) = 6
120 / (x - 19) = 6
x - 19 = 120 / 6
x - 19 = 20
x = 20 + 19
x = 39