Lina is 5 years older than Jane. Eight years ago she was three times the age of Jane.
Let's assume that Jane is (x) years old, then Lina will be
(x + 5) years old.
Eight years ago Jane was [(x) - 8] years old. Lina was [(x + 5) - 8] years old.
(x + 5) - 8 = 3*(x - 8)
x - 3 = 3x - 24
2x = 21
x = 10.5
Jane is 10.5 years old, and Lina is 15.5 years old
(Just for check: Eight years ago Jane was 2.5 y. o., and Lina was 7.5 y. o.)
Eight years ago Jane was [(x) - 8] years old. Lina was [(x + 5) - 8] years old.
(x + 5) - 8 = 3*(x - 8)
x - 3 = 3x - 24
2x = 21
x = 10.5
Jane is 10.5 years old, and Lina is 15.5 years old
(Just for check: Eight years ago Jane was 2.5 y. o., and Lina was 7.5 y. o.)