Question

даю 30 баллов задания на фото

Answer 1

Ответ:

1) в

2) в

3)

$3 {y}^{2} + 15y = 3y(y + 5)$

4)

$25 {b}^{2} - {c}^{2} = (5b - c)(5b + c)$

5)

${a}^{2} + 16 - 8a = {(a - 4)}^{2}$

6)

$4n(m - k) - (k - m) = 4n(m - k) + (m - k) = (4n + 1)(m - k)$

7)

$5xy - 10y - {x}^{2} + 2x = 5y(x - 2) - x(x - 2) = (5y - x)(x - 2) = (5 \times ( - \frac{4}{5} ) - 102)(102 - 2) = ( - 4 - 102) \times 100 = - 106 \times 100 = - 10600$

8)

$4 {a}^{2} - {b}^{2} + 2a - b = (2a - b)(2a + b) + 2a - b = (2a - b)(2a + b + 1)$

9)

$(xy + {y}^{2} )( {x}^{2} + 4x) - ( {x}^{2} + xy)( {y}^{2} + 4y) = y(x + y)x(x + 4) - x(x + y)y(y + 4) = xy(x + y)(x + 4 - (y + 4)) = xy(x + y)(x - y)$