m<A + m<B + m<C = 180
80 + 3x + 5 + 5x - 1 = 180
8x + 84 = 180
8x =96
x = 12
m<B = 3x + 5 = 3(12) + 5 = 41
m<C = 5x - 1 = 5(12) - 1 =59
and
m<A = 80
answer:
order from shortest to longest in ∆ABC
AC, AB, BC
P.S.
Smallest angle, shortest side.....
Largest angle, longer side....