How to Make the System Consistent: Solving for Alpha in an Augmented Matrix

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To determine the value of α that makes the given augmented matrix consistent, it is essential to perform Gaussian elimination. The consensus is that the system must yield either an infinite or a unique solution for consistency. After analysis, it is concluded that α must equal 2 for the system to be consistent. Engaging in Gaussian elimination is recommended as a practical approach to verify the solution. This method enhances understanding of the underlying concepts in solving augmented matrices.
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Homework Statement


\begin{array}{rrr|r} -1 & 2 & -1 & -3 \\ 2 & 3 & α-1 & α-4 \\ 3 & 1 & α & 1 \end{array}

α∈ℝ
for the augmented matrix, what value of α would make the system consistent?

Homework Equations


N/A
Answer: α=2

The Attempt at a Solution


I know that the system has to have an infinite or unique amount of solutions to be consistent and you have to perform Gaussian elimination?
 
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Cpt Qwark said:

Homework Statement


\begin{array}{rrr|r} -1 & 2 & -1 & -3 \\ 2 & 3 & α-1 & α-4 \\ 3 & 1 & α & 1 \end{array}

α∈ℝ
for the augmented matrix, what value of α would make the system consistent?

Homework Equations


N/A
Answer: α=2

The Attempt at a Solution


I know that the system has to have an infinite or unique amount of solutions to be consistent and you have to perform Gaussian elimination?

If you think that Gaussian elimination is (maybe) the way to go, then just do it! That way you will find out if it works, or not. That is the very best way to learn.
 
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I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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