Answer:
[tex]\large\boxed{f(x)=(x+8)^2-110}[/tex]
Step-by-step explanation:
[tex]\text{The vertex form of equation}\ y=ax^2+bx+c:\\\\y=a(x-h)^2+k\\\\\text{We have the equation:}\\f(x)=x^2+16x-46=x^2+2(x)(8)-46=x^2+2(x)(8)+8^2-8^2-46\\\\\text{use}\ (a+b)^2=a^2+2ab+b^2\to x^2+2(x)(8)+8^2=(x+8)^2\\\\f(x)=(x+8)^2-64-46=(x+8)^2-110[/tex]