Question

Решить уравнение 0,3(6-3y)=4,5-0,8(y-9)​

Answer 1

$0.3 \times 6 - 0.3 \times 3y = \\ 4.5 - 0.8 \times y - 0.8 \times ( - 9) \\ 1.8 - 0.9y = 4.5 - 0.8y + 7.2 \\ 1.8 - 0.9y = 11.7 - 0.8y$

$1.8 - 0.9y - 11.7 + 0.8y = 0 \\ - 9.9 - 0.1y = 0 \\ - 0.1y = 0 + 9.9 = 9.9 \\ y = 9.9 \div ( - 0.1) = - 99$