Solve the following pair of linear equations by graphical method and with the help of this find the value of ‘a’ when 4x + 3y = a

x = 3y = 6; 2x – 3y = 12

Given, x = 3y = 6, 2x – 3y = 12 and 4x + 3y = a

∴ x = 6

Putting the value of x in 2x – 3y = 12, we get

2 × 6 – 3y = 12

12 – 3y = 12

– 3y = 0

∴ y = 0

Hence the value of a is: a = 4x + 3y

= 4 × 6 + 3 × 0

= 0

So the two linear equations are:

i. 2x – 3y = 12

ii. 4x + 3y = 24

To plot the given pair of linear equations, we substitute x = 0 or y = 0

in the given linear equations to get x and y. To find more points on the

lines, take different values of x related to it and we get different values

for y from the equation.

We get the following tables for the given linear equations.

For 2x – 3y = 12

3y = 2x – 12

For 4x + 3y = 24

3y = 24 – 4x

Now plotting these two equations on graph,