(a-5)^2+2(5-a)+1 Решите pls

Question

(a-5)^2+2(5-a)+1 Решите pls

Answer 1

(a-5)(a+5)-2(a-5)+1=(a-5)(a+5-2)+1=(a-5)(a+3)+1=
a^2+3a-5a-15+1=a^2-2a-14