Question

5x+ 2y =-14 10x + 3y =- 21

Answer 1

Ответ:

(0; -7)

Объяснение:

$\left \{ {{5x + 2y = -14 | \cdot (-2)} \atop {10x + 3y = -21}} \right.\\\\\left \{ {{-10x - 4y = 28} \atop {10x + 3y = -21}} \right.\\\\\left \{ {{-10x - 4y = 28} \atop {-y = 7}} \right.\\\\\left \{ {{-10x - 4y = 28} \atop {y = -7}} \right.\\\\\left \{ {{x = 0} \atop {y = -7}} \right.$

Answer 2

$\left \{ {{5x+2y=-14}|*(-2) \atop {10x+3y=-21}} \right.\\\\+\left \{ {{-10x-4y=28} \atop {10x+3y=-21}} \right.\\ --------\\-y=7\\\\y=-7\\\\5x=-2y-14=-2*(-7)-14=14-14=0\\\\x=0\\\\Otvet:\boxed{(0;-7)}$