Question

If p(x) = x = 4, then p(x) + p(−x) = ?
(a) 0
(b) 4
(c) 2x
(d) 8

Answer 1

(d) 8

Let:
$p\left(x\right)=\left(x+4\right)$

$$\begin{gathered} \therefore p\left(-x\right)=\left(-x\right)+4 \\ =-x+4 \end{gathered}$$
Thus, we have:
$p\left(x\right)+p\left(-x\right)=\left\{\left(x+4\right)+\left(-x+4\right)\right\}$
= 4 + 4
=8