Form the pair of linear equations in the following problems,and find their solutions graphically.
$5$ pencils and $7$ pens together cost ₹ $50$,whereas $7$ pencils and $5$ pens together cost ₹ $46$. Find the cost of one pencil and that of one pen.

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(N/A) Let the cost of $1$ pencil be ₹ $x$ and the cost of $1$ pen be ₹ $y$.
According to the question,the algebraic representation is:
$5x + 7y = 50$
$7x + 5y = 46$
For $5x + 7y = 50$,we have $x = \frac{50 - 7y}{5}$.
$x$$3$$10$$-4$
$y$$5$$0$$10$

For $7x + 5y = 46$,we have $x = \frac{46 - 5y}{7}$.
$x$$8$$3$$-2$
$y$$-2$$5$$12$

By plotting these points on a graph,we observe that the lines intersect at the point $(3, 5)$.
Therefore,the cost of one pencil is ₹ $3$ and the cost of one pen is ₹ $5$.

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