Find the Tensions in the Cables

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The discussion focuses on determining the tensions in cables AB, AC, and AD based on given coordinates. The user initially calculated the unit vectors for each cable and set up equations to solve for the tensions using a force of 113 lb. After finding initial tension values, the user realized an error in the coordinates for point B, which led to incorrect results. Upon correcting the coordinates, the revised tensions were calculated as TAB = 41.9316, TAC = 41.9316, and TAD = 50.7184. The thread highlights the importance of accurate input data in solving physics problems.
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Homework Statement



Determine the tensions in cables AB, AC, and AD.


Homework Equations





The Attempt at a Solution


I mad point A (0,0,0)
B = (2.6, -4.2, 4.4)
C = (-2.6, -1.6, 4.4)
D = (0, 2.5, 4.4)
Firstly I found the unit vectos of AB, AC and AD, which are as follows

\hat{}nAB = <2.6, - 4.2, 4.4>/ 6.615134

\hat{}nAB = <0.393041i - 0.634908j + 0.665141k

\hat{}nAC = <-2.6, -1.6, 4.4>/5.35537

\hat{}nAC = <-0.48549i -0.29876j +0.821605k>

\hat{}nAD = <0i +2.5j + 4.4k>/5.06063
\hat{}nAD = oi + 0.494009j + 0.86945k

Then I took each unit vector and multiplied it by the force, 113 lb

TAB = TAB\hat{}nAB[/SUB = TAB(0.39394i - 0.634908j + 0.665141k)

TAC = TAC\hat{}nAC = TAC(-0.48549i -0.29876j + 0.821605k)

TAD = TAD\hat{}nAD =TAD(0i + 0.494009j +0.86956k)

i: 0.39304*TAB - 0.48549TAC + 0TAD

j: -0.634908TAB - 0.29876TAC + 0.494009TAD

k: 0.665141TAB + 0.821605TAC + 0.86945TAD

I then put this into a matrix and then used my calculator to solve for TAB, TAC and TAD

I got:

TAB = 39.3261
TAC = 31.9374
TAD = 69.7967

But it says my answer is wrong and I don't know where I'm going wrong. Help would be appreciated
 
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Just found my mistake. I defined the location of B incorrectly. B = (2.6, -1.6, 4.4). Using these values I get

TAB = 41.9316
TAC = 41.9316
TAD = 50.7184
 
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