(5x + 6y) (3x – 2y) = …………………… A) 8x2 – 8 xy B)

1.	(5x + 6y) (3x – 2y) = …………………… A) 8x2 – 8 xy B) 15x2 + 3xy C) 15x2 – xy D) 15x2 + 8xy – 12y2
Answer» D) 15x² + 8xy – 12y² Correct option is (D) 15x² + 8xy – 12y² (5x + 6y) (3x – 2y) \(=5x\times3x+5x\times-2y+6y\times3x+6y\times-2y\) \(=(5\times3)x^2+(5\times-2)xy+(6\times3)xy+(6\times-2)y^2\) \(=15x^2-10xy+18xy-12y^2\) = \( 15x^2+8xy-12y^2\).

(5x + 6y) (3x – 2y) = …………………… A) 8x2 – 8 xy B) 15x2 + 3xy C) 15x2 – xy D) 15x2 + 8xy – 12y2

Answer»

D) 15x² + 8xy – 12y²

Correct option is (D) 15x² + 8xy – 12y²

(5x + 6y) (3x – 2y) \(=5x\times3x+5x\times-2y+6y\times3x+6y\times-2y\)

\(=(5\times3)x^2+(5\times-2)xy+(6\times3)xy+(6\times-2)y^2\)

\(=15x^2-10xy+18xy-12y^2\)

= \( 15x^2+8xy-12y^2\).