Question

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Answer 1

$6a( - 2) = - 12a$

$2a + 3a - 6a \\ - a$

$- 7m( - 3n) \\ 21mn$

$- 3x = 9 - 3x$

x ∈ ∅

$7x = - 7x \\ x = 0$

$0x = - 55$

x ∈ ∅

$- 3ab \times 2c \\ - 6abc$