Question

how to solve this problem

Answer 1

Given: p(a) = a - 7

To find: p(a) + p(-a)

We know that p(a) = a - 7.

Therefore p(-a) = -(a - 7)

That is p(-a) = -a + 7

So now p(a) + p(-a) = a - 7 - a + 7

= 0

Hope it helps :)