Question

Find f(a+4) when f(x)=x^2+4

Answer 1

We have the next function given:

$f(x)=x^2+4$

Now, we need to find f(a+4). Then, we need to replace x=a+4 on the equation:

$f(a+4)=(a+4)^2+4$

Solve the notable product (a+4)².

Then,

(a+4)² = a²+2(a)(4)+4²

(a+4)² = a²+8a+16

Therefore, we have the next equation:

$f(a+4)=(a^2+8a+16)+4$$f(a+4)=a^2+8a+16+4$$f(a+4)=a^2+8a+20$