Роздiл 5. Лiнiйнi рiвняння та ix системи » 778 (3-6)

3) 1 + d/8 = (1-2d)/16| • 16; 16 + 2d = 1 – 2d; 2d + 2d = 1 – 16; 4d = –15; d = –15/4; d = –33/4. 4) (2-3x)/6 + 2 = x/15| • 30; 5(2 – 3x) + 60 = 2x; 10 – 15x + 60 = 2x; –15x – 2x = –60 – 10; –17x = –70; x = 70/17; x = 42/17. 5) 3 – (y+1)/9 = (2y-8)/18| • 18; 54 – 2(y + 1) = 2y – 8; 54 – 2y – 2 = 2y – 8; –2y – 2y = –8 – 54 + 2; –4y = –60; y = 15. 6) (8z-3)/2 – 4 = (1-z)/7| • 14; 7(8z – 3) – 56 = 2(1 – z) ; 56z – 21 – 56 = 2 – 2z; 56z + 2z = 2 + 21 + 56; 58z = 79; z = 79/58; z = 121/58.