Вправи 1101 - 1200 » 1126

Розв’яжіть рівняння: 1) 7х = –30 + 2х; 7х – 2х = –30; 5х = –30; х = –30 : 5; х = –6. 2) 9х + 6 = 10х; 9х – 10х = –6; –х = –6; х = 6. 3) –4 + 3х = 8х + 16; 3х – 8х = 16 + 4; –5х = 20; х = 20 : (–5); х = –4. 4) 20 – 2х = 27 + х; –2х – х = 27 – 20; –3х = 7; х = 7 : (–3); х = –21/3; 5) –17х + 20 = 7х – 28; –17х – 7х = –28 – 20; –24х = –48; х = –48 : (–24); х = 2. 6) 0,2х + 4,3 = 0,4х – 6,5; 0,2х – 0,4х = –6,5 – 4,3; –0,2х = –10,8; х = –10,8 : (–0,2); х = 54. 7) 0,6х + 100 = 0,9х + 1; 0,6х – 0,9х = 1 – 100; –0,3х = –99; х = –99 : (–0,3); х = 330. 8) 16 – 18х = –25х –12; –18х + 25х = –12 – 16; 7х = –28; х = –28 : 7; х = –4.