# Method of joints

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Can anybody tell me how I can use the method of joints here?

I know force T (22900) and force Weng (24525).

I also know that I should start in point 5

I can't figure out what my equilibrium equations should look like.

Fx= 0 en Fy=0

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What is the question that accompanies this drawing?

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I would write every vector in terms of components.   T= <-22900, 0>, Weng= <0, -24525>.   The sum of those two forces is <-22900, -24525> and the two forces, "45" and "35" must offset that.  Taking the force in vector "45" to be "x" and in vector "35" to be "y" we have "45"= <0, x> and "35"= <0.6y/1.34, 1.2y/1.34>= <0.45y, 0.90y>.  The sum of those is <0.45y, x+ 0.90y> and that must equal <22900, 24525> so we have 0.45y= 22900 and x+ 0.90y= 24525.  From the first y= 22900/0.45= 50,889.  Then the second is x+ 45800= 24525 so x= 24525- 45800= -21275.

So vector "45" is <0, -21275> and "35" is <50899(.45), 50899(.90)>= <22904.55, 45809.1>.

The others are done the same way.

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