Friction vs Work

1. The problem statement, all variables and given/known data

An 18.5 kg block is dragged over a rough,
horizontal surface by a constant force of 129 N
acting at an angle of angle 29.3◦ above the
horizontal. The block is displaced 64.8 m,
and the coefficient of kinetic friction is 0.115. The
acceleration of gravity is 9.8 m/s2 .

How can I figure out the magnitude of the work done by the force of friction!


2. Relevant equations

W = F*D

3. The attempt at a solution
I attempted to do -129 times the displacment but, its not correct :(
 
please post your steps...
 

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