Завдання 1301 - 1402 » 1306

Спрости вираз: 1) (–0,7x + 0,6y) · 5 – 3(0,4y – 1,5x – 1) – (2,7 – 8) = –0,7x · 5 + 0,6y · 5 – 3 · 0,4y + 3 · 1,5x + 3 – 2,7x + 8 = –3,5x + 3y – – 1,2y + 4,5x + 3 – 2,7x + 8 = –1,7x + 1,8y + 11; 2) 2/9(2,7 – 11/2x) – 11/6(1,8 – 2/7x) = (2 ∙ 27)/(9 ∙ 10) – (2 ∙ 3)/(9 ∙ 2)x – (7 ∙ 9)/(6 ∙ 5) + (7 ∙ 2)/(6 ∙ 7)x = 3/5 – 1/3x – 21/10 + 1/3x= (6 - 21)/10 = (-15)/10 = –1,5.