Question

preciso das contas
urgente ​

Answer 1

Explicação passo-a-passo:

$(-{2\over10}).(-{5\over4}).(-{7\over3})=\\ \\ (-{2.5.7\over10.4.3})=-{70\over120}=-{7\over12}\\ \\ ===============\\ \\ ({28\over45}).(-{25\over14})=\\ \\ simplifica~~28~~e~~14~~por~~7\\ 26~~e~~45~~por~~5\\ \\ ({\not28^4\over\not45_9}).({-{\not25^5\over\not14_2})= ({4\over9}).(-{5\over2})=-{20\over18}=-{10\over9}$