Question

Дам 35 балов срояно зарание спасибо

Answer 1

$1)\left \{ {{a=6} \atop {2a-b=18}} \right.\\\\\left \{ {{a=6} \atop {2*6-b=18}} \right.\\\\\left \{ {{a=6} \atop {12-b=18}} \right.\\\\\left \{ {{a=6} \atop {b=12-18}} \right. \\\\\left \{ {{a=6} \atop {b=-6}} \right.\\\\Otvet:\boxed{a=6,b=-6}$

2)

15x + 2y = 75

2y = 75 - 15x

y = - 2,5x

2y = - 5x

75 - 15x = - 5x

75 = - 5x + 15x

75 = 10x

x = 7,5

y = - 2,5x = - 2,5 * 7,5 = - 18,75

Ответ : (7,5 ; - 18,75)