Q.120. Let . If f(a) = a, then what is the value of a?
(A) 7
(B) 14
(C) 21
(D) 6
x^2-27x+196
a^2-27a+196=a
a^2-27a-a+196=0
a^2-28a+196=0
a^2-14a-14a+196=0
a(a-14)-14(a-14)=0
(a-14)(a-14) are the factors so a=14
a^2-27a+196=a
a^2-27a-a+196=0
a^2-28a+196=0
a^2-14a-14a+196=0
a(a-14)-14(a-14)=0
(a-14)(a-14) are the factors so a=14