Question

Помогите( Алгебра....( Очень нужна помощь....

Answer 1

1)
$\frac{4 {c}^{2} - 25 {x}^{2} }{4 {c}^{2} + 20cx + 25 {x}^{2} } = \frac{(2c - 5x)(2c + 5x)}{ {(2c + 5x)}^{2} } = \frac{2c - 5x}{2c + 5x}$
2)
$\frac{6ab - 9 {b}^{2} }{4 {a}^{2} - 9 {b}^{2} } = \frac{3b(2a - 3b)}{(2a - 3b)(2a + 3b)} = \frac{3b}{2a + 3b}$
3)
$\frac{ 2{x}^{3} y - 8x {y}^{3} }{2 x{y}^{2} - {x}^{2}y } = \frac{2xy( {x}^{2} - 4 {y}^{2} )}{xy(2y - x)} = \frac{2xy(x - 2y)(x + 2y)}{ - xy(x - 2y)} = - 2(x + 2y) = - 2x - 4y$

Answer 2

$1) \\ \frac{(2c - 5x)}{(2c + 5x)} = \frac{2c - 5x}{2c + 5x} \\ \\ 2) \\ \frac{3b(2a - 3b)}{(2a - 3b)(2a + 3b)} = \frac{3b}{2a + 3b} \\ \\ 3) \\ \frac{xy(2x {}^{2} - 8y {}^{2}) }{xy(2y - x)} = \frac{2(x {}^{2} - 4 {y}^{2} )}{ - (x - 2y)} = \frac{2(x - 2y)(x + 2y)}{ - (x - 2y)} = 2 \times ( - 1)(x + 2y) = - 2 \times 1(x + 2y) = - 2x - 4y$