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Let $N$ denote the set of all natural numbers. Define two binary relations on $N$ as $R_1 = \{(x,y) \in N \times N : 2x + y= 10\}$ and $R_2 = \{(x,y) \in N\times N : x+ 2y= 10\} $. Then
Both $R_1$ and $R_2$ are transitive relations
Both $R_1$ and $R_2$ are symmetric relations
Range of $R_2$ is $\{1, 2, 3, 4\}$
Range of $R_1$ is $\{ 2, 4, 8\}$
Solution
Here,
${R_1} = \left\{ {\left( {x,y} \right) \in N \times N:2x + y = 10} \right\}$
${R_2} = \left\{ {\left( {x,y} \right) \in N \times N:x + 2y = 10} \right\}$
For ${R_1};2x + y = 10$ and $x,y \in N$
So, possible values for $x$ and $y$ are:
$x = 1,y = 8$ i.e. $(1,8);$
$x = 2,y = 6\,$ i.e. $(2,6);$
$x = 3,y = 4$ i.e. $\,(3,4)$ and
$x = 4,y = 2\,$ i.e. $(4,2)$.
${R_1} = \left\{ {(1,8),(2,6),(3,4),(4,2)} \right\}$
Therefore, Range of ${R_1}$ is $\left\{ {2,4,6,8} \right\}$
${R_1}$ is not symmetric
Also,${R_1}$ is not transitive because
$(3,4),(4,2) \in {R_1}$ but $\,(3,2) \notin {R_1}$
Thus, options $A,B$ and $D$ are incorrect.
For ${R_2};x + 2y = 10$ and $x,y \in N$
So, possible values for $x$ and $y$ are:
$x = 8,y = 1\,$i.e.$\,(8,1);$
$x = 6,y = 2$i.e.$(6,2);$
$x = 4,y = 3$i.e.$(4,3)$ and
$x = 2,y = 4$i.e.$(2,4)$
${R_2} = \left\{ {(8,1),(6,2),(4,3),(2,4)} \right\}$
Therefore, Range of ${R_2}$ is $\left\{ {1,2,3,4} \right\}$
${R_2}$ is not symmetric and transitive.