Question

if 4x²+9y²=69,xy=1,then find tje value of (2x+3y)​

Answer 1

$= > {4x}^{2} + {9y}^{2} = 69$

$= > {(2x)}^{2} + {(3y)}^{2} = 69$

$= > {(2x + 3y)}^{2} - 2.2x.3y = 69$

$= > {(2x + 3y)}^{2} - 12xy = 69$

$= > {(2x + 3y)}^{2} = 69 + 12$

$= > {(2x + 3y)}^{2} = 81$

$= > (2x + 3y) = \sqrt{81}$

$= > (2x + 3y) = 9$