Решите уравнения по математике 6 класс

a) 0,3(5x - 7) = 3(0,2x + 3,2)
1,5x - 2,1 = 0,6x + 9,6
0,9x = 11,7
x = 13

6) 4(1,2x + 3,7) - 2,8 = 5,2x
4,8x + 14,8 - 2,8 = 5,2x
1,6x = -12
x = -7,5

6) (4 1/6 * x + 11 1/4) * 4/15 = 2/3 * x + 5 2/3
(25x/6 + 45/4) * 4/15 = 2/3x + 17/3
5x/6 + 45/16 = 2/3x + 17/3
5x/6 - 2/3x = 17/3 - 45/16
x/6 = -47/48
x = -7,83

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