SOLUTION: Factoring Trinomials by Trial and Error 20x^2+29x+5

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Question 57393: Factoring Trinomials by Trial and Error
20x^2+29x+5

Found 2 solutions by funmath, Nate:
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
Factoring Trinomials by Trial and Error
20x^2+29x+5
The possible factors of 20x^2 are:
20x*x, 2x*10x, 4x*5x,
These are the possible first term of each parntheis.
:
The possible facotrs of 5 are:
1*5, and 5*1
:
Let's start the trial:
(20x+1)(x+5)=20x^2+100x+x+5=20x^2+101x+5 ERROR
(20x+5)(x+1)=20x^2+20x+5x+5=20x^2+25x+5 ERROR
(2x+1)(10x+5)=20x^2+10x+10x+5=20x^2+20x+5 ERROR
(2x+5)(10x+1)=20x^2+2x+50x+5=20x^2+52x+5 ERROR
(4x+1)(5x+5)=20x^2+20x+5x+5=20x^2+25x+5 ERROR
(4x+5)(5x+1)=20x^2+4x+25x+5=20x^2+29x+5 Correct, this is it!!!
If you practice enough, you'll know which numbers to try. There are more methodical methods to use.
Happy Calculating!!!


Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
To get 5 you multiply: 1 and 5
(something + 5)(something + 1)
(10x + 5)(2x + 1) Work?
20x^2 + 10x + 10x + 5
20x^2 + 20x + 5 No
(2x + 5)(10x + 1) Work?
20x^2 + 50x + 2x + 5 No
(5x + 5)(4x + 1) Work?
20x^2 + 20x + 5x + 5 No
(4x + 5)(5x + 1) Work?
20x^2 + 25x + 4x + 5
20x^2 + 29x + 5 Yes