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help me please, i have no idea what im supposed to be doing and my teacher isnt much help so im hoping someone else can help me

help me please, i have no idea what im supposed to be doing and my teacher isnt much-example-1
User Thezar
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1 Answer

2 votes

Answer:

(4, 2 ) and (2, 4 )

Explanation:

xy = 8 → (1)

y = - x + 6 → (2)

substitute y = - x + 6 into (1)

x(- x + 6) = 8

- x² + 6x = 8 ( subtract 8 from both sides )

- x² + 6x - 8 = 0 ( multiply through by - 1 )

x² - 6x + 8 = 0 ← in standard form

(x - 4)(x - 2) = 0 ← in factored form

equate each factor to zero and solve for x

x - 4 = 0 ⇒ x = 4

x - 2 = 0 ⇒ x = 2

substitute these values into (2) for corresponding values of y

x = 4 : y = - 4 + 6 = 2 ⇒ (4, 2 )

x = 2 : y = - 2 + 6 = 4 ⇒ (2, 4 )

User Nemron
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