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The number of values of k for which the ...

The number of values of `k` for which the lines `(k+1)x+8y=4ka n dk x+(k+3)y=3k-1` are coincident is __________

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To find the number of values of \( k \) for which the lines \( (k+1)x + 8y = 4k \) and \( kx + (k+3)y = 3k - 1 \) are coincident, we will use the condition for two lines to be coincident. The lines are coincident if the ratios of the coefficients of \( x \), \( y \), and the constant terms are equal. ### Step 1: Identify the coefficients From the first line \( (k+1)x + 8y = 4k \): - Coefficient of \( x \) (let's call it \( a_1 \)) = \( k + 1 \) - Coefficient of \( y \) (let's call it \( b_1 \)) = \( 8 \) - Constant term (let's call it \( c_1 \)) = \( 4k \) From the second line \( kx + (k+3)y = 3k - 1 \): - Coefficient of \( x \) (let's call it \( a_2 \)) = \( k \) - Coefficient of \( y \) (let's call it \( b_2 \)) = \( k + 3 \) - Constant term (let's call it \( c_2 \)) = \( 3k - 1 \) ### Step 2: Set up the equations based on the condition for coincident lines The lines are coincident if: \[ \frac{a_1}{a_2} = \frac{b_1}{b_2} = \frac{c_1}{c_2} \] This gives us the following equations: 1. \( \frac{k + 1}{k} = \frac{8}{k + 3} \) 2. \( \frac{8}{k + 3} = \frac{4k}{3k - 1} \) ### Step 3: Solve the first equation From the first equation: \[ \frac{k + 1}{k} = \frac{8}{k + 3} \] Cross-multiplying gives: \[ (k + 1)(k + 3) = 8k \] Expanding: \[ k^2 + 4k + 3 = 8k \] Rearranging: \[ k^2 - 4k + 3 = 0 \] Factoring: \[ (k - 3)(k - 1) = 0 \] Thus, \( k = 3 \) or \( k = 1 \). ### Step 4: Solve the second equation From the second equation: \[ \frac{8}{k + 3} = \frac{4k}{3k - 1} \] Cross-multiplying gives: \[ 8(3k - 1) = 4k(k + 3) \] Expanding: \[ 24k - 8 = 4k^2 + 12k \] Rearranging: \[ 4k^2 - 12k + 8 = 0 \] Dividing by 4: \[ k^2 - 3k + 2 = 0 \] Factoring: \[ (k - 2)(k - 1) = 0 \] Thus, \( k = 2 \) or \( k = 1 \). ### Step 5: Identify common roots The common root from both equations is \( k = 1 \). ### Conclusion The number of values of \( k \) for which the lines are coincident is \( 1 \). ### Final Answer The number of values of \( k \) is \( \boxed{1} \). ---

To find the number of values of \( k \) for which the lines \( (k+1)x + 8y = 4k \) and \( kx + (k+3)y = 3k - 1 \) are coincident, we will use the condition for two lines to be coincident. The lines are coincident if the ratios of the coefficients of \( x \), \( y \), and the constant terms are equal. ### Step 1: Identify the coefficients From the first line \( (k+1)x + 8y = 4k \): - Coefficient of \( x \) (let's call it \( a_1 \)) = \( k + 1 \) - Coefficient of \( y \) (let's call it \( b_1 \)) = \( 8 \) - Constant term (let's call it \( c_1 \)) = \( 4k \) ...
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