F3數學　二元二次方程　有沒人可以解答？

( X + 1 )^2 / 2 - ( Y - 1 )^2 / 2 = 1 ---------- ( 1 )
X - Y = 1 ---------------------------------------( 2 )

從方程(2)中, X = Y + 1 --------------------------( 3 )

將(3) 代入方程(1),

( Y + 1 + 1 )^2 / 2 - ( Y - 1 )^2 / 2 = 1

( Y + 2 )^2 - ( Y - 1 )^2 = 2

(Y^2 + 4Y + 4) - ( Y^2 -2Y + 1 ) = 2

Y^2 + 4Y + 4 - Y^2 + 2Y - 1 - 2 = 0

6Y = -1

Y = - 1/6

將 Y = - 1/6 代入方程( 2 ),

X = - 1/6 + 1

X = -1/6 + 6/6

X = 5/6

答案: X=5/6 Y=-1/6

As follow AS~~~~

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