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soldi70 [24.7K]

2 years ago

7

If x + y = 12 and xy = -5, calculate the value of 1/x + 1/y.

1 answer:

Paul [167]2 years ago

8 0

$\dfrac{1}{x}+\dfrac{1}{y}=\dfrac{y}{xy}+\dfrac{x}{xy}=\dfrac{x+y}{xy}=\dfrac{12}{-5}=-\dfrac{12}{5}=-2,4$

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