Question

розв‘язати способом додавання

Answer 1

$\displaystyle\bf\\\left \{ {{6x - 4y = 10 \: \: | \times 3 } \atop {11x + 3y = 39 \: \: | \times4 }} \right. \\ \displaystyle\bf\\ + \left \{ {{18x - 12y = 30} \atop {44x + 12y = 156 }} \right. \\ \\ 18x + 44x = 30 + 156 \\ 62x = 186 \\ x = 186 \div 62 \\ x = 3 \\ \\ 6 \times 3 - 4y = 10 \\ 18 - 4y = 10 \\ 4y = 18 - 10 \\ 4y = 8 \\ y = 8 \div 4 \\ y = 2$

Ответ: ( 3 ; 2 )