1) 15c * 3 = 45c
18 * 4d = 72d
12p * 5g = 60pg
2) 19y - 4y + y = 16y = 16 * 7 = 112
37b - 8b - 10b + 19 = 19b + 19 = 19 * 12 + 19 = 247
3) а) 15x - 8x = 56 б)4f + 2f = 42 в) 6a + a - 6a = 66 г) 5t + 2t - 7t = 7
7x = 56 6f = 42 a = 66 7t - 7t = 7
x = 56 :7 f = 42 : 6 0 ≠7
х = 8 f = 7 решений нет
4) ((90213 - 263 * 51) : 160 - 66) : 18 = ((90213 - 13413) : 160 - 66) : 18 =
(76800 : 160 - 66) : 18 = (480 - 66) : 18 = 414 : 18 = 23