Answer: 9
Step-by-step explanation:
Given
The function is [tex]x^2-6x+c[/tex]
To make it a perfect square, compare it with [tex](a-b)^2=a^2+b^2-2ab[/tex]
Here,
[tex]x=a,\\-6x=-2ab\\\\\therefore b=3[/tex]
So, c must be square of b i.e. 9
[tex]x^2-6x+c\Rightarrow x^2-6x+9\\\Rightarrow (x-3)^2[/tex]
Therefore, value of c is 9.