SOLUTION: how do i factor trinomials? ex: Xsquared+4X+3 i need step bt step help , thanks

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Question 333056: how do i factor trinomials?
ex:
Xsquared+4X+3
i need step bt step help , thanks

Found 2 solutions by benazir.sj@gmail.com, solver91311:
Answer by benazir.sj@gmail.com(109) About Me  (Show Source):
You can put this solution on YOUR website!
x^2+4x+3
=x^2+3x+1x+3
=x(x+3)+1(x+3)
=(x+1)(x+3)

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


This process is good for quadratic trinomials where the lead coefficient is 1. Given a quadratic trinomial of the form:



Step 1: Write .

Step 2: Put in the signs. If the sign on the constant, that is the term, is positive, then the signs in the factors are the same as the sign on the first degree, that is the term. If the sign on the constant term is negative then one of the binomials has a and the other has a .

Step 3: Find all factors and such that

Step 4:

If the sign on the constant term was , then select a pair of factors from the group of factor pairs developed in Step 3 such that . Insert and into or depending on the sign on the term.

If the sign on the constant term was , then select a pair of factors from the group of factor pairs developed in Step 3 such that . Insert and into or such that whichever of or has the larger absolute value goes with the sign that is on the original term.

Your example:



Step 1:



Step 2: Both signs , so:



Step 3: Factors of 3 are 1 and 3.

Step 4: 3 plus 1 is 4, hence:



Use FOIL to multiply the two binomials to check your work. The product should be the original trinomial.

Trinomials with a lead coefficient other than 1 are a little trickier. Basically you are looking for numbers , , , and , such that





and



John

My calculator said it, I believe it, that settles it