Find each of the following products:

(3x2 + 5x - 9) × (3x – 5)

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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