Question

Помогите с 2,3,4 (хотя бы с 1)

Answer 1

Ответ:

1)

$15 - 3x = 11 + 2x \\ - 6x = - 4 \\ x = \frac{2}{3}$

2)

$\frac{y { }^{9} }{y {}^{6} } = y {}^{3}$

4)

$x { }^{2} - 25 - 3x + {x}^{2} = 2x {}^{2} - 3x - 25 = 2 +( - 1) {}^{2} - 3 \times ( - 1) - 25 = - 20$