After a constant acceleration of 2.1 m/s/s at 31.7 degrees above the +x-axis is applied by the motors of a boat for 7.75 seconds, the boat is moving at 59.1 m/s at 43 degrees above the +x-axis. What was the initial velocity of the boat? (Give your answer in terms of a positive rotation from the +x-axis, in degrees)

Vf = Vo + a*t = 59.1m/s[43o].

Vo + 2.1[31.7o]*7.75 = 59.1[43].
Vo + 16.3[31.7o = 59.1*Cos43+59.1*sin43.
Vo+16.3*Cos31.7+16.3*sin31.7=43.2+40.3i.
Vo + 13.9 + 8.6i = 43.2 + 40.3i.
Vo=43.2 + 40.3i - 13.9 - 8.6i=29.3+31.7i

Vo = 43.2m/s[47.3o], CCW from +X-axis.