Find each of the following products:(3x2 + 5x - 9) × (3x – 5)

1.	Find each of the following products:(3x2 + 5x - 9) × (3x – 5)
Answer» By using horizontal method, We have; = (3x² + 5x – 9) × (3x – 5) = 3x(3x² + 5x – 9) – 5(3x² + 5x – 9) = 9x³ + 15x² – 27x – 15x² - 25x + 45 By arranging the expression in the form of descending powers of x, We get; = 9x³ + 15x² – 15x² – 27x – 25x + 45 = 9x³ – 52x + 45

Answer»

By using horizontal method,

We have;

= (3x² + 5x – 9) × (3x – 5)

= 3x(3x² + 5x – 9) – 5(3x² + 5x – 9)

= 9x³ + 15x² – 27x – 15x² - 25x + 45

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

We get;

= 9x³ + 15x² – 15x² – 27x – 25x + 45

= 9x³ – 52x + 45

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