Question

Дам 20 балов
$3(6 x - 7) + 21 =$
$9(3 - 4x) + 5x -6 =$
$21(10 - 3y)27y + 30 =$

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Answer 1

Объяснение:

1) 18х-21+21=18х

2) 27-36х+5х-6=21-31х

Answer 2

Объяснение:

$3(6x - 7) + 21 = 18x - 21 + 21 = 18x$

$9(3 - 4x) + 5x - 6 = 27 - 36x + 5x - 6 = 21 - 31x$

$21(10 - 3y) \times 27y + 30 = 567y \times (10 - 3y) + 30 = 5670y - 1701y {}^{2} + 30 = - 1701 y{}^{2} + 5670y + 30$