multiply
(-5-p)(5+p)
-1 (p+5)(p-5)
in general
a^2-b^2 = (a+b)(a-b)
so this is
-1(p^2-25)
which is
25-p^2
or use distributive property as I did in your other problem
(-5-p)(5+p)
in general
a^2-b^2 = (a+b)(a-b)
so this is
-1(p^2-25)
which is
25-p^2
or use distributive property as I did in your other problem