Answer:
[tex]F(2)=C-12[/tex]
Step-by-step explanation:
Given: [tex]F(x)=x^2-8x+C[/tex]
To find: value of [tex]F(2)[/tex]
Solution:
[tex]F(x)=x^2 - 8x + C\\=x^2-2(4)x+C[/tex]
Add and subtract [tex]4^2[/tex] in the left side of the equation
[tex]F(x)=x^2-2(4)x+4^2-4^2+C[/tex]
Use formula: [tex](a-b)^2=a^2-2ab+b^2[/tex]
[tex]F(x)=(x-4)^2-4^2+C\\=(x-4)^2+C-16[/tex]
Put [tex]x=2[/tex]
[tex]F(x)=(x-4)^2+C-16\\F(2)=(2-4)^2+C-16\\=4+C-16\\=C-12[/tex]