How do you factor $4x^2 + 34x + 42$ ?

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Answer 1 · 2016-05-02T11:30:09

$2(2x+3)(x+7)$

notice that all the coefficients are even

$=>2(2x^2+17x+21)$

The only whole number factors of 2 are: {1,2}
The only whole number factors of 21 are: {3,7}

Notice that $2xx7+3=17$

$=>2(2x+3)(x+7)$

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Check by multiplying out the brackets.

$=>2(2x^2+14x+3x+21) =2(2x^2+17x+21)$

How do you factor 4x^2 + 34x + 424x^2 + 34x + 42?