if 2x + 3y = 8 and xy = 2, find the value of 4X2 + 9y2. -Maths 9th

if 2x + 3y = 8 and xy = 2, find the value of 4X2 + 9y2. -Maths 9th
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 Given 2x+3y=8 and xy=2,  formula, (a+b)2=a2+b2+2ab ∴(2x+3y)2=4x2+9y2+2(2x)(3y) (2x+3y)2=4x2+9y2+12xy 82=4x2+9y2+12(2) ∴4x2+9y2=64−24=40
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