Question

решите систему уровнений​

Answer 1

$\left \{ {{8x + 7y = 0} \atop {3x + 2y = 15}} \right. \\ \left \{ {{8x + 7y = 0} \atop {x = 5 - \frac{2}{3} y}} \right. \\ 8( 5 - \frac{2}{3} y) + 7y = 0 \\ \boldsymbol{y = - 24} \\ x = 5 - \frac{2}{3} \times ( - 24) \\ \boldsymbol{x = 21}$

(х ; у) = (21 ; -24)

Answer 2

Объяснение:

$\begin {cases}8x + 7y = 0 \: \: \: | \times 2 \\ 3x + 2y = 15 \: \: \: | \times ( - 7)\end {cases}\Leftrightarrow\begin {cases}16x + 14y = 0 \\ - 21x - 14y = - 105\end {cases} \\ - 5x = - 105 \\ x = 21 \\ 168 + 7y = 0 \\ y = - 24$

Ответ : (х;у)=(21 ; -24)