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.

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(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 ₹ $5$.

Explore More

Similar Questions

On comparing the ratios $\frac{a_{1}}{a_{2}}, \frac{b_{1}}{b_{2}}$ and $\frac{c_{1}}{c_{2}},$ find out whether the following pair of linear equations are consistent or inconsistent.
$5x - 3y = 11$; $-10x + 6y = -22$

One says,"Give me a hundred,friend! $I$ shall then become twice as rich as you". The other replies,"If you give me ten,$I$ shall be six times as rich as you". Tell me what is the amount of their (respective) capital?

Which of the following pairs of linear equations has a unique solution,no solution,or infinitely many solutions? In case there is a unique solution,find it by using the cross-multiplication method.
$x - 3y - 7 = 0$
$3x - 3y - 15 = 0$

Difficult
View Solution

Form the pair of linear equations for the following problem and find their solution by the substitution method.
The difference between two numbers is $26$ and one number is three times the other. Find the numbers.

The students of a class are made to stand in rows. If $3$ students are extra in a row,there would be $1$ row less. If $3$ students are less in a row,there would be $2$ rows more. Find the number of students in the class.

Difficult
View Solution

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo