Question

5х+2у=10 7х +4у=8 система додаваннябудь ласка​

Answer 1

Ответ:

x = 4

y = -5

Объяснение:

$\left \{ {{5x + 2y = 10} \atop {7x+4y=8}} \right. \\x = \frac{10-2y}{5} \\7*\frac{10-2y}{5} + 4y = 8\\7(10-2y) + 20y = 40\\70 - 14y +20y = 40\\6y = -30\\y = -5\\\\5x + 2*(-5) = 10\\5x - 10 = 10\\5x = 20\\x = 4$