К 3,,,,,,,,,,,,=!=,=,,=,,=,
<span>2/3y - 1/3 = 5/9y
</span>2/3y- 5/9y = 1/3
(6/9-5/9)у=1/3
1/9 у=1/3
у=1/3 :1/9
у = 3
3/4y - 2/3 = 7/12
3/4y = 7/12 + 2/3
3/4у= 7/12+8/12
3/4у= 15/12
у=15/12:3/4
у= 5/3 = 1 2/3
6. 5
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15. 18
14. 10
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50. 70
Вот что смогла)
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