Question

8у-3(2у-3)=7у-20у+8
5(2у-9)+6у=4(-3у-2)-21
5у+7(3-4=3(5-2у)-6
7у-4(3у+5)=2-3(4у-9


решите срочно дом 12 Баллов​

Answer 1

Ответ:

$1)8y - 6y + 3 - 7y + 20y - 8 = 0 \\ 15y = 5 \\ y = \frac{5}{15} = \frac{1}{3} \\ 2)10y - 45 + 6y = - 12y - 8 - 21 \\ 10y + 6y + 12y = 45 - 8 - 21 \\ 28y = 16 \\ y = \frac{16}{28} = \frac{4}{7} \\ 4)7y - 12y - 20 = 2 - 12y + 27 \\ 7y = 49 \\ y = 7 \\ 3)5y + 7(3 - 4) = 3(5 - 2y) - 6 \\ 5y - 7 = 15 - 6y - 6 \\ 11y = 16 \\ y = \frac{16}{11} \\ 3)5y + 7(3 - 4y) = 3(5 - 2y) - 6 \\ 5y + 21 - 28y = 15 - 6y - 6 \\ 5y + 6y +28y = 15 - 6 - 21 \\ 39y = - 12 \\ y = - \frac{12}{39} \\ y = - \frac{4}{13}$

в 3 у в скобках не дописали? решила и так и так.