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Answered

if x²+y²=20 and x-y=6 how is x.y?
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Answer :

Answer:

xy = - 8

Step-by-step explanation:

note that

(x - y)² = x² + y² - 2xy , that is

6² = 20 - 2xy

36 = 20 - 2xy ( subtract 20 from both sides )

16 = - 2xy ( divide both sides by - 2 )

- 8 = xy

KONRAD509IN

[tex](x-y)^2=x^2-2xy+y^2[/tex]

Therefore

[tex]6^2=20-2xy\\36=20-2xy\\2xy=-16\\xy=-8[/tex]

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