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You have a sign error in the third equation in the top right group. Also, I couldn't read some of it. Looks like ##-6yz,\delta z##.
Homework Statement:: Find the force in point D, both Dx and Dy
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Since there is resistance to compression from the fluid in cavity C, you can consider D to be an anchor to ground in order to determine instantaneous forces and torques for that particular geometry of the mechanism.
Note that the angle of 75° formed between both levers is key in calculating Dx.
