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Sari is factoring the polynomial 2x2 + 5x + 3. What is the missing number in her factorization? 2x2 + 5x + 3 = (2x +[ ? ])(x + 1)

User Jdinunzio
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2 Answers

6 votes

Answer:2x-3

Step-by-step explanation:

User Christian Ulbrich
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4 votes

Answer: 3

Step-by-step explanation:

The polynomial is:


2x^2+5x+3 (1)

We want to factorize it as follows:


(2x+C)(x+1)

where C is the unknown number we want to find.

Solving explicitely the last equation,


(2x+C)(x+1)=2x^2 +2x +Cx +C=2x^2 +(2+C)x+C (2)

We want eq.(2) to be identical to eq.(1). From the last term, we see immediately that it must be C=3, and 2+C=5. So the missing number is 3, and the factorization is


(2x+3)(x+1)

User DanMan
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