Reasoning/Method of choice
Factoring and Zeros
Explain and Justify
100

Give one appropriate factoring method you would choose for the quadratic x2 + 5x + 6, and briefly state why that method is efficient here.

What is Guess and Check! Because the leading coefficient is 1, and we know 2 and 3 multiply to 6 and add to 5.

100

Factor and find zeros for x2 - x - 6.

What is (x-3)(x+2), and x=3 and x=-2?

100

Given x3  +5x2 + 4x + 20, identify the factoring method you would use and write one sentence to justify it.

What is factor by grouping because you can factor out an x2 out of the first 2 terms and a 4 out of the second two terms to make them both equal x+5.

200

For 2x2 + 7x + 3, name a method you would use and give a one-sentence reason.

What is the AC method or the Slide and Divide method? Explanation: the leading coefficient is not 1.

200

Factor and find zeros for 2x2 - x - 6.

What is (2x+3)(x-2), and x=-3/2 and x=2. 

200

For 5x2 + 6x + 1, pick a method and give a brief reason why that method is preferred

What is the use of slide-and-divide, because a≠1 and ac=5 have integer factor pairs 1 and 5, and 1+5=6. 

300

For 3x2 - 2x - 8, which method would you prefer and why (one or two sentences)?

What is Grouping? Explanation: : multiply a*c = 3(-8) = -24. Find pair +4 and -6 (since 4 + (-6) = -2), split the middle term, and factor by grouping. 

300

Factor and find zeros for 2x2 +12x + 10.

What is (2x+2)(x+5), and x=-1 and x=-5?

300

 For x2+x−1, which method would you choose and why? Provide the zeros.

What is the quadratic formula, or completing the square, because the trinomial does not factor nicely with integers? Zeros:\frac{-1 \pm \sqrt{5}}{2} .

400

For x2 + 6x + 10, which factoring approach would you select and why?

What is completing the square or the quadratic formula? Explanation: Because we know the quadratic will have complex roots. 

400

Factor and find zeros for 6x2 - 13x + 6.

What is (2x−3)(3x−2), and x=3/2,  x=2/3?

400

For 4x2+9x+2, identify a what method you would use and explain why. 

What is grouping? Because ac=8, find integers summing to 9  (1 and 8), split the middle term: 9x=8x+x, factor by grouping to get (4x+1)(x+2)(4x+1)(x+2). Zeros: x=−14,  x=−2.

500

For 4x2 + 4x + 1, identify the best factoring method, explain your reasoning (include how you recognized the structure), and list the zeros.

What is the recognition of a perfect square trinomial or grouping? Explanation: varies, zeros x=-1/2 with multiplicity 2. 

500

Factor and find zeros for 9x2 -30x + 25; explain your factoring choice and show zeros.

What is recognizing the perfect square trinomial or grouping? Factor: (3x-5)2, Zeros are x=5/3 with multiplicity 2.

500

Given 2x2−4x+5 identify the best strategy, fully justify it, and state the zeros.

What is the quadratic formula? Zeros: (1±isqrt.6)/2.

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