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For which value of k will the following ...

For which value of k will the following pair of linear equations have no solutions?
`3x+ y=1`
`(2k-1) x + (k-1)y= 2k+1`

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The correct Answer is:
To determine the value of \( k \) for which the given pair of linear equations has no solutions, we need to analyze the conditions under which a system of linear equations is inconsistent. The given equations are: 1. \( 3x + y = 1 \) (Equation 1) 2. \( (2k-1)x + (k-1)y = 2k + 1 \) (Equation 2) For the system to have no solutions, the following condition must hold: \[ \frac{a_1}{a_2} = \frac{b_1}{b_2} \quad \text{and} \quad \frac{c_1}{c_2} \neq \frac{a_1}{a_2} \] Where: - \( a_1 = 3 \), \( b_1 = 1 \), \( c_1 = 1 \) (from Equation 1) - \( a_2 = 2k - 1 \), \( b_2 = k - 1 \), \( c_2 = 2k + 1 \) (from Equation 2) ### Step 1: Set up the ratios We will first set up the ratios: \[ \frac{3}{2k - 1} = \frac{1}{k - 1} \] ### Step 2: Cross-multiply the ratios Cross-multiplying gives us: \[ 3(k - 1) = 1(2k - 1) \] ### Step 3: Expand both sides Expanding both sides results in: \[ 3k - 3 = 2k - 1 \] ### Step 4: Rearrange the equation Now, we will rearrange the equation to isolate \( k \): \[ 3k - 2k = -1 + 3 \] \[ k = 2 \] ### Step 5: Verify the condition for no solutions Now we need to ensure that this value of \( k \) satisfies the second part of the condition: \[ \frac{c_1}{c_2} \neq \frac{a_1}{a_2} \] Substituting \( k = 2 \): - \( c_2 = 2(2) + 1 = 5 \) - \( a_2 = 2(2) - 1 = 3 \) Now check: \[ \frac{c_1}{c_2} = \frac{1}{5} \quad \text{and} \quad \frac{a_1}{a_2} = \frac{3}{3} = 1 \] Since \( \frac{1}{5} \neq 1 \), the condition is satisfied. ### Final Answer Thus, the value of \( k \) for which the pair of linear equations has no solutions is: \[ \boxed{2} \]
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