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I'm stuck on this:
Given that x − y = 8, and that xy ≤ 240, find the maximum value of (x + y).
Original post by dimapos32
Since x - y = 8, x = 8 + y.

xy ≤ 240
(y+8)y ≤ 240
y^2 + 8y - 240 ≤ 0

y = [ -20 , 12 ]
max value of y = 12 --> x = 20

So the maximum value is 32 ( x + y = 20 + 12 = 32 )


so what is the maximum value exactly??Could you explain please?
Original post by Chelsea12345
so what is the maximum value exactly??Could you explain please?


Original post by dimapos32

So the maximum value is 32 ( x + y = 20 + 12 = 32 )


:smile:
Original post by dimapos32
:smile:


Thankyou!

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