Question

Please please help me​

Answer 1

$1)3k - 2k \\ = k(3 - 2) \\ = k(1) \\ = k$

$2) {5x}^{2} - 10x - {8x}^{2} + x \\ = {5x}^{2} - {8x}^{2} - 10x + x \\ = - 3 {x}^{2} - 9x \\ = - 3x(x - 3)$

$3) - (m + n) + 2(m - 3n) \\ = - m - n + 3m - 6n \\ = - m + 2m - n - 6n \\ = m - 7n$

Hope you could get an idea from here.

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