Tension Problem x and y components?

AI Thread Summary
A 70 kg man hangs from two cables inclined at 60 degrees, with a horizontal force of 250 N applied to the right, keeping him stationary. The weight of the man is calculated as 686 N. The problem involves setting up two equations based on the x and y components of forces: one for horizontal equilibrium and one for vertical equilibrium. The equations are A*cos(120) + B*cos(60) + 250 = 0 for the x-component and A*sin(120) + B*sin(60) + 686 = 0 for the y-component. The solution requires substituting one variable in terms of the other to solve for the tensions in the cables.
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Tension Problem x and y components??

Homework Statement



A man of mass 70.0 kg hangs by 2 cables A and B each inclined at 60.0 degrees to the horizontal.

A horizontal pulling force F is applied to the man pulling to the right. The man remains stationary. If F has magnitude 250 N, find the magnitudes of the tension in the 2 cables.


Homework Equations



F=w=mg
A+B+F+W=0



The Attempt at a Solution



(70 kg)(9.8)=686 N
the downward W force is 686 N

x-component
Ax+Bx+F=0
Acos120+Bcos60+250=0

y-component
Ay+By+W=0
Asin120+Bsin60+686=0

I know there is a system of equations here and that i can use substitution or trigonometric triangles but I am not sure how to approach either of these methods. Any help would be great. Sorry i don't have a picture, i hope it makes sense.
 
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Acos120+Bcos60+250=0
Asin120+Bsin60+686=0

Evaluate the cos and sin terms, and one has two equations and two unknowns, which one should be able to solve.
 
hmm sorry it still doesn't make sense to me I am not sure how to put B in terms of A or A in terms of B and then after i find these numbers how to go about finding the tensions of the cables.
 
First of all the weight is negative (sin270, right?)

Now turn all those sins and cos's into decimals, and rewrite the first equation so that it reads " A = blablablah + B(blah)"

then substitute that for the "A" in the second equation.
 
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