Verified answer

498(3)

9 (143 - 13x) = 234

143 - 13x = 234 : 9

143 - 13x = 26

13x = 143 - 26

13x = 117

x = 117 : 13

x = 9

проверка 9(143 - 13*9) = 9*(143 - 117) = 9*26 = 234

500(2)

17x - x + 5x - 19 = 170

16x + 5x = 170 + 19

21x = 189

x = 189 : 21

x = 9