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The number of values of $k$ for which the system of linear equations, $(k + 2) x + 10y = k,\,\,kx + (k + 3)y = k - 1$ has no solution, is
Infinitely many
$3$
$1$
$2$
Solution
Here, the equations are;
$(k+2)x+10y=k$
and $ kx+(k+3)y=k-1$.
These equations can be written in the form of $Ax=Bas$
$\left[ {\begin{array}{*{20}{c}} {k + 2}&{10}\\ k&{k + 3} \end{array}} \right]\left[ {\begin{array}{*{20}{c}} x\\ y \end{array}} \right] = \left[ {\begin{array}{*{20}{c}} k\\ {k – 1} \end{array}} \right]$
For the system to have no solution
$\left| A \right| = 0$
$ \Rightarrow \left[ {\begin{array}{*{20}{c}} {k + 2}&{10}\\ k&{k + 3} \end{array}} \right] = 0$
$ \Rightarrow \left( {k + 2} \right)\left( {k + 3} \right) – k \times 10 = 0$
$ \Rightarrow {k^2} – 5k + 6 = \left( {k – 2} \right)\left( {k – 3} \right) = 0$
$\therefore k = 2.3$
For $k=2,$ equations become:
$4x + 100y = 2$ and $2x + 5y = 1$
hence infintie number of solutions.
For $k=3$, equations becomes;
$5x + 10y = 3$
$3x + 6y = 2$
$4$ hence no solution.
$\therefore $ req. number of values of $k$ is $1$.