Question

Срочно помогите решить

Answer 1

1.

а) x^2 - 9 / x - 3 = (x - 3)(x + 3) / x - 3 = x + 3;

б) x^2 + 2x + 1 / x + 1 = (x + 1)^2 / x + 1 = x + 1;

2.

x^2 - x / 2y • y / x - 1 = y(x^2 - x) / 2y(x - 1) = xy( x - 1) / 2y(x - 1) = x/y.

3.

a) 2x + 1 = 3 - x

2x + x = 3 - 1

3x = 2

x = 2/3

Ответ: 2/3.

б) 2x - 1 / 3 + x + 1 / 2 = 2

4x - 2 + 3x + 3 / 6 = 2

7x + 1 / 6 = 2

7x + 1 = 2 • 6

7x + 1 = 12

7x = 12 - 1

7x = 11

x = 1 4/7

Ответ: 1 4/7.

Answer 2

номер 1

$a) \: \frac{x ^{2} - 9 }{x - 3} = \frac{(x - 3)(x + 3)}{x - 3} = x + 3 \\ b) \: \frac{ {x}^{2} + 2x + 1}{x + 1} = \frac{(x + 1)^{2} }{x + 1} = x + 1$

номер 2

$\frac{ {x}^{2} - x}{2y} \times \frac{y}{x - 1} = \frac{ {x}^{2}y - xy }{2yx - 2y} = \frac{xy(x - 1)}{2y( x - 1)} = \frac{x}{2}$

номер 3

$a) \: 2x + 1 = 3 - x \\ \: \: \: \: \: 2x + x = 3 - 1 \\ \: \: \: \: \: 3x = 2 \\ \: \: \: \: \: x = 2 \div 3 \\ \: \: \: \: \: x = \frac{2}{3}$
$b) \: \frac{2x - 1}{3} + \frac{x + 1}{2} = 2 \: | \times 6 \\ \: \: \: \: \: 6 \times \frac{2x - 1}{3} + 6 \times \frac{x + 1}{2} = 6 \times 2 \\ \: \: \: \: \: 4x - 2 + 3x + 3 = 12 \\ \: \: \: \: \: 7x = 12 + 2 - 3 \\ \: \: \: \: \: 7x = 11 \\ \: \: \: \: \: x = 11 \div 7 \\ \: \: \: \: \:x = 1\frac{4}{7}$