Ответ
3•4+2•2-5=12+4-5=11-у
3a) C⁴ * C⁷ :C⁹ = C⁴⁺⁷⁻⁹ = C²
б) (a⁴)³ * a = a¹² * a = a¹³
в) (- 2x)⁴ = 16x⁴
4a) 20³ * 0,5³= (20 * 0,5 )³ = 10³ = 1000
б) (4 * 2⁵) / 2⁷ = (2² * 2⁵) / 2⁷ = 2⁷ / 2⁷ = 1
5) [(y²)³]⁴ = (y⁶)⁴ = y²⁴
Х - х/12 = -55/12
11х/12 = -55/12
11х = -55
х = -55/11
х = -5