11,1,-9,-19,-29

You have to employ the formula

Explicit formula is given as a

_{n}= a_{1}+ (n – 1)dFrom the given sequence: 11,1,-9,-19,-29

a = 11, d = 10 and n = 5

a

_{n}= 11 + (n – 1)10a

_{n}= 11 +10n - 10a

_{n}= 10n - 1 and that is your explicit formula.