Номер 489.
Решите уравнение:1) 21(18 + х) = 714;2) 16(4х — 34) = 608;3) 12(152 + 19 х) = 2 052;4) (152х + 32) · 6 = 192.
Ответ:1) 21(18 + х) = 714.18 + х = 714 : 21.18 + х = 34.х = 34 — 18.х = 16.2) 16(4х — 34) = 608.4х — 34 = 608 : 16
4х — 34 = 38.4х = 38 + 34.4х = 72.х = 72 : 4.х = 18.3) 12)152 + 19х) = 2 052.152 + 19х = 2 052 : 12.
152 + 19х = 171.19х = 171 — 152.19х = 19.х = 19 : 19.х = 1.4) (152х + 32) · 6 = 192.152х + 32 = 192 : 6.
152х + 32 = 32.152х = 32 — 32.152х = 0.х = 0.