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If 4x^2+y^2=40 and x y=6, find the value...

If `4x^2+y^2=40` and `x y=6,` find the value of `2x+ydot`

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`We have,
'(2x+y)² = (2x)² + y² + 2*2x*y
⇒(2x + y)² = (4x² +y²) + 4xy
=(2x+y)^2 =40+4*6
=(2x+y)^2
=64
=2x+y=± sqrt(64)
=2x+y= ± 8'`
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