Q. 4x2+28x+49Which of the following is equivalent to the given expression?Choose 1 answer:(A) (2x+7)2(B) (2x+49)2(C) (4x+7)2(D) (4x+49)2
Recognize the structure: Recognize the structure of the given expression.The given expression 4x2+28x+49 is a quadratic expression. We will try to factor it, looking for a binomial squared that matches this expression.
Factor the quadratic expression: Factor the quadratic expression.We notice that the first term 4x2 is a perfect square, as (2x)2=4x2. The last term 49 is also a perfect square, as 72=49. The middle term 28x is twice the product of the square roots of the first and last terms, since 2×2x×7=28x. This suggests that the expression is a perfect square trinomial.
Write as a binomial squared: Write the expression as a binomial squared.Since the expression fits the pattern of a perfect square trinomial, we can write it as (2x+7)2, which expands to 4x2+2×2x×7+72, which simplifies to 4x2+28x+49.
Verify by expanding the binomial: Verify the answer by expanding the binomial.To ensure that (2x+7)2 is indeed equivalent to the given expression, we expand it: (2x+7)(2x+7)=4x2+14x+14x+49=4x2+28x+49. This matches the original expression exactly.
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