Y² + X² + bXY = 25
Y + 6X = -35
Подставим Х = -6; Y = 1
1 + 36 + b·(-6) = 25
37 - 6b = 25
6b = 12
b = 2
ПРОВЕРКА
1 + 36 + 2·(-6) = 25 → 37 - 12 = 25 → 25 ≡ 25
1 + 6·(-6) = -35 → 1 - 36 = -35 → -35 ≡ -35
Y - XY = -10
b(Y - X) + 1 = Y
Подставим Х = -1,5; Y = -4
b(-4 + 1,5) + 1 = -4
-2.5b + 1 = -4
-2,5b = -5
b = 2
ПРОВЕРКА
-4 -1,5·4 = -10 → -4 -6 = -10 → -10 ≡ -10
2(-4 + 1,5) + 1 = -4 → 2·(-2,5) + 1 = -4 → -5 + 1 = -4 → -4 = - 4