Factor 2x 4 - 20x 2 - 78.

2 answers:

8 0

Divide everything by 2: 2(x4-10x2-39). Now factor: 2(x2+3)(x2-13) or B. We know it's not A because the last variable is negative so the signs must be different. :)

const2013 [10]3 years ago

6 0

2(x^4 - 10x^2 - 39)
2(x^2 - 13)(x^2 + 3)

Letter B

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