Question

розвязати спамобом підстановки {5x+y=10 {2x-y=4​

Answer 1

Ответ:

{5x + y = 10

{2x - y = 4

{y = 10 - 5x

{2x - y = 4

2x - (10 - 5x) = 4

2x - 10 + 5x = 4

7x = 4 + 10 = 14 / : 7

x = 2

y = 10 - 5 * x = 10 - 5 * 2 = 10 - 10 = 0

Answer 2

Объяснение:

$\left \{ {{5x+y=10} \atop {2x-y=4}} \right.\ \ \ \ \left \{ {{5x+2x-4=10} \atop {y=2x-4}} \right. \ \ \ \ \left \{ {{7x=14\ |:7} \atop {y=2x-4}} \right. \ \ \ \ \left \{ {{x=2} \atop {y=2*2-4}} \right. \ \ \ \ \left \{ {{x=2} \atop {y=0}} \right. .$

Ответ: x=2    y=0.