Even function: f(-x) = f(x). If you replace x by -x you should find the same function.
Odd function: f(-x) = -f(x). If you replace x by -x you find the same function with opposite sign;
Is f(-x) = f(x)?
f(x) = (x+4)² = x² + 8x +16
f(-x) = (-x+4)² = x² - 8x + 16, then it's not an even function
Is f(-x) = -f(x)?
f(-x) = (-x+4)² = x² + 8x + 16 , then it's not an odd function
It is neither an even nor an odd function