Вправи 1101 - 1200 » 1110

Розв’яжіть рівняння: 1) –Зу – 9у + 5у = 2,1; –7у = 2,1; У = 2,1: (–7); у = –0,3. 2) –2,4m + 3,8m + 1,2m = –0,052; 2,6m = –0,052; m = –0,052 : 2,6; m = –0,02. 3) –3/7а + 5/6а – 8/21а = –1/49; –18/42а + 35/42а – 16/42а = –1/49; 1/42а = –1/49; а = –1/49 : 1/42; а = –42/49; а = –6/7; 4) 3,4у + у∙(–8,1) – (–2,2)∙у = –10; 3,4у – 8,1у + 2,2у = –10; –2,5у = –10; у = –10: (–2,5); у = 4.