Simple question about how to solve a force problem.

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To solve the force problem, the user needs to find the horizontal (Fh) and vertical (Fv) forces using the equations provided. The equations are Fh = cos(60)(AB) - cos(45)(BC) = 0 and Fv = sin(60)(AB) + sin(45)(BC) - 1000 = 0. The discussion emphasizes the importance of substituting values from one equation into the other to solve for the unknowns AB and BC. Clarification is sought on the identities of AB and BC, which are presumed to be reaction forces. The user is encouraged to follow a substitution method to find the solution step by step.
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I have to find the Force Horizontally and Vertically.

My equation for Fh is cos(60)(AB) - cos(45)(BC) = 0
My equation for Fv is sin 60 (AB) + sin 45 (BC) – 1000 = 0

I don't recall how to move things around, what to divide etc. Basically i need a step by step explained so i can learn and recall hopefully how.

These were rules for what to do also:

You can use either equation to write an expression for either AB or BC, then substitute the value you find in the OTHER equation. You must substitute into the other equation in order to solve for an answer

Please Help!
 
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mstehman said:
I have to find the Force Horizontally and Vertically.

My equation for Fh is cos(60)(AB) - cos(45)(BC) = 0
My equation for Fv is sin 60 (AB) + sin 45 (BC) – 1000 = 0

I don't recall how to move things around, what to divide etc. Basically i need a step by step explained so i can learn and recall hopefully how.

These were rules for what to do also:

You can use either equation to write an expression for either AB or BC, then substitute the value you find in the OTHER equation. You must substitute into the other equation in order to solve for an answer

Please Help!

Welcome to the PF.

What are AB and BC? Are they angles? I'd presume not, since you list other angles as arguments to the trig functions, but it's hard to be sure.

Is there a diagram that goes with this problem that you can post? That would help a lot in giving you some hints on how to proceed.
 
Here is the photo
 

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does that help at all?
 
mstehman said:
I have to find the Force Horizontally and Vertically.

My equation for Fh is cos(60)(AB) - cos(45)(BC) = 0
My equation for Fv is sin 60 (AB) + sin 45 (BC) – 1000 = 0
I assume that what you call AB is the reaction force RA and BC is the force RC.

So you have two equations and two unknowns.

I don't recall how to move things around, what to divide etc. Basically i need a step by step explained so i can learn and recall hopefully how.

These were rules for what to do also:

You can use either equation to write an expression for either AB or BC, then substitute the value you find in the OTHER equation. You must substitute into the other equation in order to solve for an answer
This is a description of solving equations by substitution. Here's an example worked out: http://www.helpalgebra.com/onlinebook/substitutionmethod.htm"

Give it a try.
 
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