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Homework Statement:
 Find the forces in hinches B, C and D.
Homework Equations:
 Sum forces = 0 and sum torques = 0
First subsystem:
$$C_x + F_{DE} \cos(45) = 0$$
$$C_y + F_{DE} \sin(45) + 20= 0$$
$$F_{DE} \sin(45) \times 25 + 20 \times 150= 0$$
Second subsystem:
$$B_x  C_x = 0$$
$$B_y  C_y  A_y  20= 0$$
$$F \times 150 + A_y \times 60  C_x \times 30 = 0$$
Third subsystem:
$$B_x  F_{DE} \cos(45) = 0$$
$$A_y B_y  F_{DE} \sin(45)= 0$$
$$A_y \times 60+ F_{DE} \sin(45) \times 55 = 0$$
Problem is that I have 9 equations and only 6 unknwowns.
$$C_x + F_{DE} \cos(45) = 0$$
$$C_y + F_{DE} \sin(45) + 20= 0$$
$$F_{DE} \sin(45) \times 25 + 20 \times 150= 0$$
Second subsystem:
$$B_x  C_x = 0$$
$$B_y  C_y  A_y  20= 0$$
$$F \times 150 + A_y \times 60  C_x \times 30 = 0$$
Third subsystem:
$$B_x  F_{DE} \cos(45) = 0$$
$$A_y B_y  F_{DE} \sin(45)= 0$$
$$A_y \times 60+ F_{DE} \sin(45) \times 55 = 0$$
Problem is that I have 9 equations and only 6 unknwowns.
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