First write both vectors in terms of their horizontal and vertical components.
G = (40.3 m)(cos(-35.0º) x + sin(-35.0º) y)
G = (33.0 x - 23.1 y) m
(where x and y are the unit vectors that point in the positive horizontal and vertical directions, respectively)
H = (63.3 m)(cos 270º x + sin 270º y)
H = (-63.3 y) m
Then the vector sum is
G + H = (33.0 x - 86.4 y) m
which has a magnitude of
|| G + H || = √[33.0^2 + (-86.4)^2] = 92.5 m
