Question 1040461
{{{3x^2-2x-21=0}}}


Look for the combinations you need and find which of them works.

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(3x  3)(x  7 )
diagonal terms, 3x and 21x


(3x  7)(x  3)
diagonal terms, 7x and 9x; so this should work;
just choose the proper arithmetic operations in each binomial.
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