20n squared -47n +213x squared +10x +4

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Kitamiliseakekw · Accepted Answer

20      n          2        −  47  n  +  21 factors into (4x-7)(5x-3)  3      x          2        +  10  x  +  4 cannot be factored. You will need to usethe binomial theorem to find the roots.

comAttitRize8 · Accepted Answer

20      n          2        −  47  n  +  21Factors of 20 : 1, 20 ; 2, 10; 4,5Factors of 21: 1, 21 ; 3, 7You can do this by trial and error and just try differentvaraitions, but if you cant get that you can do the &quot;ACmethod&quot;  but thats a lot longer in my opinion, esp withthe A term and C term being large.Trial and error. We want to try variations of the factors tillwe find one that works.Try 4 and 5 for 20 and 7 and 3 for 21(4n-7)(5n-3)Multiplying the terms to check to see if we get 47n for themiddle term 12n + 35n = 47nSince the last sign is positive, I know both signs have to bepositve or both negative. Since the middle sign is negative, bothsign are negative.(4n - 7)(5n -3)  3      x          2        +  10  x  +  4Factors of 3 are 3 and 1Factors of 4 are 1 and 4, 2 and 2Since everything is positive are signs are positive.(3x + 4)(x+1)   3x + 4x = 7x; No,does not equal 10x(3x + 1) (x + 4) 12x + x = 13x; No(3x + 2) (x + 2) 6x + 2x= 8x; NoAttempted all variations of the factors and none of themwork.  3      x          2        +  10  x  +  4 is a prime polynomial.

20n squared -47n +21 3x squared +10x +4

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