(x-y)²=12,(x+y)=16,求x²+y²的值

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(x-y)²=12,(x+y)=16,求x²+y²的值
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(x-y)²=12,(x+y)=16,求x²+y²的值
(x-y)²=12,(x+y)=16,求x²+y²的值

(x-y)²=12,(x+y)=16,求x²+y²的值
(x-y)²=12, (1)
(x+y)=16
两边平方得:
(x+y)²=256 (2)
(1)+(2)得:
2(x²+y²)=12+256
2(x²+y²)=268
x²+y²=268÷2=134