Only for c = 49 the given expression is the square of a binomial.
We want to find the values of c such that:
[tex]4x^2 + 14x + c[/tex]
Is the square of a binomial.
Remember that:
[tex](a + b)^2 = a^2 + 2ab + b^2[/tex]
Now we can rewrite our expression as:
[tex](2x)^2 + 2*7*x + c[/tex]
If you compare that with the general binomial expansion, we can see:
[tex]a = 2x[/tex]
[tex]b = 7[/tex]
Then c must be equal to 7 squared:
[tex]7^2 = 49 = c[/tex]
Only for c = 49 the given expression is the square of a binomial.
If you want to learn more about binomials:
https://brainly.com/question/13602562
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