Question

решите пж
1) x-3y=-2
2x+3y=14
2) 5x+y=3
-3x-4y=5

Answer 1

$x - 3y = - 2 \\ 2x + 3y = 14 \\ \\ Складываем \\ 3x = 12 \\ x = 12 \div 3 \\ x = 4 \\ \\ 4 - 3y = - 2 \\ 3y = 4 - ( - 2) \\ 3y = 4 + 2 \\ 3y = 6 \\ y = 6 \div 3\\ y = 2 \\ \\Ответ: \:( 4 \: ; \: 2) \\ \\ 5x + y = 3 \: \: | \times 4 \\ - 3x - 4y = 5 \\ \\ 20x + 4y = 12 \\ - 3x - 4y = 5 \\ \\ Складываем \\17x = 17 \\x = 17 \div 17 \\ x = 1 \\ \\ 5 \times 1 + y = 3 \\5 + y = 3 \\ y = 3 - 5 \\ y = - 2 \\ \\ Ответ: (1 \: ; \: - 2)$