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## Homework Statement

If the weight of the boom is negligible compared with the applied 45-kN load, determine the cable tensions T1 and T2 and the force acting at the ball joint at A.

## Homework Equations

## The Attempt at a Solution

I have successfully calculated the tensions in T1 and T2 to be 71.1512 kN and 60.749kN respectively.

But I've been having a lot of difficulty calculating the forces at point A. My attempt is as follows:

ƩF

_{x}= 0

-T2 + T1cos(θx) + Ax

θx = arccos(9/15.81) where 15.81 is the length of the cable T1

Ax = 60.749 - 71.1512cos(55.304)

Ax = 20.2481

ƩF

_{y}= 0

θy = arctan (15/9)

θy = 59.036

0 = t1cos(59.036) - 45 + Ay

Ay = 8.393

ƩF

_{z}= 0

θz = arctan(10.2956/12) where 10.2956 is the length from A to C.

θz = 40.62857

0 = Az - 71.1512cos(40.62857)

Az = 53.999

A = [itex]\sqrt{}20.2481^2 + 8.393^2 + 53.999^2[/itex]

A = 58.278

It says my answer is wrong and I don't see where I'm going wrong. Help would be greatly appreciated.