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1)x^2+14x+49

=(x+7)(x+7)

2)4x^2-40

=4(x^2-10)

=4(x-10^1/2)(x+10^1/2)

3)2x^2+8x+6

=(2x+6)(x+1)

4)3X^2-300

3(x-10)(x+10)

5)4x^2-20x-24

=4(x^2-5x-6)

=4(x-6)(x+1)

6)8x^2-40x+50

=(8x-10)(x-5)

7)-7x^2-21x+28

=-7(x^2+3x-4)

=-7(x-4)(x+1)

8)8x^2-18

=8(x^2-9)

=8(x+3)(x-3)

9)20x^2+50x+30

=10(2x+3)(x+1)

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