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)#