Question

Solve the given pair of linear equation by substitution method
3x-2y = 11; 2x + 3y = 4​

Answer 1

Step-by-step explanation:

3x-2y = 11 (eqn. no. 1)

2x+3y = 4 (eqn. no. 2)

(equal the value of x or y in both the eqn)

multiplying the eqn no. 1 by 2

2(3x-2y = 11)

6x - 4y = 11

6x - 4y - 11 = 0 (eqn no. 3)

multiplying the eqn no. 2 by 3

3(2x+3y = 4)

6x + 9y = 12

6x + 9y - 12 = 0 (eqn no. 4)

(subtracting eqn no. 4 by eqn no. 3 to eliminate x)

6x + 9y - 12 - (6x - 4y - 11 ) = 0

6x + 9y - 12 - 6x + 4y + 11 = 0

13y - 1 = 0

13y = 1

y = 1/13

putting the value of y in the eqn no. 1

3x-2y = 11 (eqn. no. 1)

3x - 2(1/13) = 11

3x - 2/13 = 11

39x - 2 = 143

39x = 143 - 2

39x = 141

x = 141/39

x = 47/13