{ x + y = 14
{ 1/x + 1/y = 7/24
{ x = 14 - y
{ 1/(14-y) + 1/y = 7/24
(y+14-y)/(y(14-y)) = 7/24
24*14 = 7y(14 - y)
48 = 14y - y²
y² - 14y + 48 = 0 D = b²-4ac = 196-192 = 4
y₁ = (14+2)/2 = 8 x₁ = 14-8 = 6
y₂ = (14-2)/2 = 6 x₂ = 14-6 = 8
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Ответ: {6; 8}, {8; 6}
Ответ:
3 # 4=90
Пошаговое объяснение:
a # b = (2a + 3b) (7a - 16).
3 # 4 = (2•3 + 3•4) (7•3- 16)=
=(6+12)(21-16)=18•5=90