Answer: 12.25
Step-by-step explanation:
A perfect square trinomial is written as \(ax^2+2abx+b^2\) , where
first term \(ax\) = square of first term of binomial
second term=2abx=twice the product of both terms of binomial.
and third term 'c'=square of last term of binomial
In the given polynomial , \(x^2+7x+c\), a=1
and 2ab = 7
When we put value of a =1, we get
\(2(1)b=7\\\Rightarrow\ b=\frac{7}{2}\)
Hence, in place of the question mark makes the given polynomial a perfect square trinomial =\(b^2=(\frac{7}{2}^2=12.25\)
