Номер 1098
1) (–4 + 9) + (–8) = 5 + (–8) = –3; –4 + (9 + (–8)) = –4 + 1 = –3
Отже, (–4 + 9) + (–8) = –4 + (9 + (–8))
2) (12 + (–3)) + (–5) = 9 + (–5) = 4; 12 + ((–3) + (–5)) = 9 + (–5) = 4
Отже, (12 + (–3)) + (–5) = 12 + ((–3) + (–5))
1) (–4 + 9) + (–8) = 5 + (–8) = –3; –4 + (9 + (–8)) = –4 + 1 = –3
Отже, (–4 + 9) + (–8) = –4 + (9 + (–8))
2) (12 + (–3)) + (–5) = 9 + (–5) = 4; 12 + ((–3) + (–5)) = 9 + (–5) = 4
Отже, (12 + (–3)) + (–5) = 12 + ((–3) + (–5))