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Simplify the following quadratic expressions
1) 2x^2 -3x -9
2) 3x^2 +5x +2​

1 Answer

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Answer:

Below in bold.

Explanation:

1) 2x^2 -3x -9

2 * -9 = -18. We need 2 numbers whose product is -18 and whose sum is -3. They are -6 and + 3. So:

= 2x^2 - 6x + 3x - 9

= 2x(x - 3) + 3(x - 3)

= (2x + 3)(x - 3)

2) 3x^2 + 5x +2​

Now 3 * 2 = 6 We need to numbers whose product is + 6 and whose sum is +5. Theres are + 3 and + 2>

= 3x^2 + 3x + 2x + 2

= 3x(x + 1) + 2(x + 1)

= (3x + 2)(x + 1)

=

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