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Determine the number of solutions for the following system of linear equations. If there is only one solution, find the solution.No solution? Only one solution? Infinitely many solutions?

Determine the number of solutions for the following system of linear equations. If-example-1
User Nie Xing
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1 Answer

19 votes
19 votes

Answer:

No solution

Step-by-step explanation:

Given the below system of linear equations;


\begin{gathered} -5x+y+3z=2\ldots\ldots\ldots.\ldots\text{Equation 1} \\ -x+2y-z=2\ldots\ldots\ldots\ldots\ldots\text{Equation 2} \\ 6x-3y-2z=-1\ldots\ldots\ldots\ldots\text{.Equation 3} \end{gathered}

We'll follow the below steps to solve the given system of equations;

Step 1: Make y in Equation 1 the subject of formula by adding 5x to both sides and subtracting 3z from both sides as seen below;


\begin{gathered} -5x+5x+y+3z-3z=2+5x-3x \\ y=2+5x-3z\ldots\ldots\ldots.....\ldots..\text{Equation 4} \end{gathered}

Step 2: Put Equation 4 into Equation 2, we'll have;


\begin{gathered} -x+2(2+5x-3z)-z=2 \\ -x+4+10x-6z-z=2 \\ 9x-7z=-2\ldots\ldots\text{.}\mathrm{}\text{Equation 5} \end{gathered}

Step 3: Put Equation 4 into Equation 3;


\begin{gathered} 6x-3(2+5x-3z)-2z=-1 \\ 6x-6-15x+9z-2z=-1 \\ -9x+7z=5\ldots\ldots\text{.}\mathrm{}\text{Equation 6} \\ \end{gathered}

Step 4: Add Equation 5 and Equation 6;


\begin{gathered} (9x-7z)+(-9x+7z)=-2+5_{} \\ 9x-7z-9x+7z=3 \\ 0=3 \end{gathered}

We can see that adding Equation 5 and 6 gave us 0 = 3 which is not a valid equation, therefore, we can say that the given system of equations has no solution.

User Yatg
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