Find each of the following products: (3x + 2y – 4) × (x – y + 2)

1.	Find each of the following products: (3x + 2y – 4) × (x – y + 2)
Answer» By using horizontal method, We have; = (3x + 2y – 4) × (x – y + 2) = x(3x + 2y – 4) – y(3x + 2y – 4) + 2(3x + 2y – 4) = 3x² + 2xy – 4x – 3xy – 2y² + 4y + 6x + 4y – 8 By arranging the expression in the form of descending powers of x, We get; = 3x² – 4x + 6x + 2xy – 3xy – 2y² + 4y + 4y – 8 = 3x² + 2x – xy – 2y² + 8y – 8

Answer»

By using horizontal method,

We have;

= (3x + 2y – 4) × (x – y + 2)

= x(3x + 2y – 4) – y(3x + 2y – 4) + 2(3x + 2y – 4)

= 3x² + 2xy – 4x – 3xy – 2y² + 4y + 6x + 4y – 8

By arranging the expression in the form of descending powers of x,

We get;

= 3x² – 4x + 6x + 2xy – 3xy – 2y² + 4y + 4y – 8

= 3x² + 2x – xy – 2y² + 8y – 8

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