Question

системи рівнянь способом додавання. {3x-8y=-19, {5x+16y=27​

Answer 1

$\displaystyle\bf\\\left \{ {{3x - 8y = - 19 \: \: | \times 2 } \atop {5x + 16y = 27 }} \right. \\ \displaystyle\bf\\ + \left \{ {{6x - 16y = - 38} \atop {5x + 16y = 27 }} \right. \\ \\ 6x + 5x = 27 - 38 \\ 11x = - 11 \\ x = - 11 \div 11 \\ x = - 1 \\ \\ 3 \times ( - 1) - 8y = - 19 \\ - 3 - 8y = - 19 \\ 8y = - 3 + 19 \\8 y = 16 \\ y =1 6 \div 8 \\ y = 2$

Ответ: ( - 1 ; 2 )