Question

Решите самостоятельнуб работу плз

Answer 1

1)

$- 7(a + b - c) = \\ - 7 \times a - 7 \times b - 7 \times ( - c) = \\ - 7a - 7b + 7c$

$- 10(m - n + k) = \\ - 10 \times m - 10 \times ( - n) - 10 \times k = \\ - 10m + 10n - 10k$

2)

$15ab - 12ac = 3a \times 5b - 3a \times 4c = \\ 3a(5b - 4c)$

$16ab - 24ac = 8a \times 2b - 8a \times 3c = \\ 8a (2b - 3c)$

3)

$2 \frac{7}{9} \times ( - 5 \frac{8}{19} ) - 1 \frac{7}{9} \times ( - 5 \frac{8}{19} ) = \\ - 5 \frac{8}{19} \times (2 \frac{7}{9} - 1 \frac{7}{9} ) = - 5 \frac{8}{19} \times 1 = \\ - 5 \frac{8}{17}$

$- 1 \frac{7}{15} \times \frac{11}{13} + ( - 1 \frac{7}{15} ) \times \frac{2}{13} = \\ - 1 \frac{7}{15} \times ( \frac{11}{13} + \frac{2}{13} ) = - 1 \frac{7}{15} \times 1 = \\ - 1 \frac{7}{15}$

4)

$7(2x - 3) + 4(3x - 2) = \\ 14x - 21 + 12x - 8 = \\ 26x - 29$

$- 8(2 - 2y) + 4(3 - 4y) = \\ - 16 + 16y + 12 - 16y = \\ - 16 + 12 = - 4$