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3x^2+6x+16.

Find the number that allows this trinomial to be re written into a perfect square

User Shaktimaan
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1 Answer

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Final answer:

To convert the trinomial 3x^2+6x+16 into a perfect square, the number needed is -13, which when adjusted for in the constant term, would allow the trinomial to be rewritten as a perfect square binomial squared.

Step-by-step explanation:

To convert the trinomial 3x^2+6x+16 into a perfect square, we can use the method of completing the square. Completing the square involves creating a binomial that when squared will produce the original quadratic trinomial. First, we need to focus on the x terms of the trinomial.

The coefficient of x^2 is 3, so our binomial will have the form (√x^2 + m)^2, where m is the number we are trying to find. For a perfect square trinomial, the middle term is twice the product of the square root of the a-coefficient and m. In our case, the middle term is 6x, and the square root of the a-coefficient is √3. As such, we have:

2 × √3 × m = 6x

√3 × m = 3x

m = 3x / √3

m = √3 × x

Now that we have m, we know that the binomial is (√3x + √3)^2, which results in:

3x² + 2√3 × 3x + 3

Since we initially had a constant term of 16, and our perfect square has a constant term of +3, the number needed to be added to 16 to make the trinomial a perfect square is:

Required number = Constant term of perfect square - Original constant term

Required number = 3 - 16

Required number = -13

Therefore, the number that allows the trinomial 3x^2+6x+16 to be rewritten into a perfect square is -13.

User Greg Weber
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