Solutions to systems of equations

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Discussion Overview

The discussion centers around the solvability of a system of equations involving two variables, ##x## and ##y##, and their relationship to parameters ##A## and ##B##. Participants explore the implications of having either the variables or the parameters as unknowns, considering the conditions under which solutions may be determined or undetermined.

Discussion Character

  • Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions whether it is reasonable to have ##x## and ##y## known while ##A## and ##B## remain unknown.
  • Another participant asserts that having ##x## and ##y## known with ##A## and ##B## unknown is a straightforward calculation.
  • A follow-up question is posed regarding the status of parameters ##a_1, a_2, b_1, b_2## as known or unknown.
  • A participant clarifies that they were considering ##a_1, a_2, b_1, b_2## as unknowns, suggesting that this leads to an undetermined system with either no solution or infinite solutions.
  • In contrast, another participant claims that ##A## and ##B## have unique values that depend on the parameters, asserting that they are never undetermined.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the system of equations, with some suggesting it can be undetermined while others argue that ##A## and ##B## are uniquely defined. The discussion remains unresolved regarding the conditions that lead to determined versus undetermined systems.

Contextual Notes

The discussion highlights the dependence on the definitions of known and unknown parameters, as well as the implications of different assumptions about the variables involved.

kent davidge
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The set of equations $$A = a_1 x + a_2y$$ ¨$$B = b_1 x + b_2 y$$ can be solved for the unkowns ##x## and ##y##. Does it make sense to have ##x## and ##y## be known and instead ##A## and ##B## unkown?
 
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That is called a straightforward calculation
 
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Likes   Reactions: Kaushik and kent davidge
kent davidge said:
Does it make sense to have ##x## and ##y## be known and instead ##A## and ##B## unknown?

What would ##a_1, a_2,b_1,b_2## be? Known or unknown?
 
Stephen Tashi said:
What would ##a_1, a_2,b_1,b_2## be? Known or unknown?
Sorry for not clarifying, I was regarding them as unkowns. Otherwise the solution would be obvious as @BvU pointed out.

I figured out the answer to my question. In such case, the system would be undetermined. It has either no solution of infinite solutions.
 
A and B have a unique value each that depends on all the parameters on the right side. They are never undetermined.
 

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