Trinomial Where A ≠ 1
- When factoring trinomials where a ≠ 1, two main methods are used: Guess and Check and Factoring by Grouping.
- Guess and Check.
- When using this method, you simply try every solution you can until it factors out.
- Ex. 2x2+9x-5
- Find the Factors of -5 = 1,-5 and -1,5
- Guess and Check
- (2x-1)(x+5) or (2x+1)(x-5)
- the first one solves to be 2x2+ 9x-5 (the right answer) and the second one solves to be 2x2-9x-5 (the wrong answer)
- When using this method, you simply try every solution you can until it factors out.
- Factoring by Grouping.
- When using this method, you separate the two factorial statements by undergoing a series of steps
- Factor: ax2+bx+c
- First, multiply a and c=ac
- Second, find two factors of ac whose sum is b.
- Third, split the middle term by using the two factors.
- Then, group the first two and last two terms.
- Last, factor out the GCF from each group and rewrite.
- Example: 6x2-13x-5
- 6*-5=-30
- -15+2=-13 and -15*2=-30
- 6x2-15x+2x-5
- (6x2-15x)+(2x-5)
- 3x(2x-5)+(2x-5)
- (3x+1)(2x-5)
- Example: 6x2-13x-5
- When using this method, you separate the two factorial statements by undergoing a series of steps
- Guess and Check.
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