Question

find the number of the following pair of linear equation 3x-3y=5
7x-2y=2

Answer 1

Given equation :-

3x - 3y = 5 ..... ( i ) × 2

7x - 2y = 2 .... ( ii ) × 3

Sub ( ii ) × 3 from ( i ) × 2

6x - 6y - ( 21x - 6y ) = 10 - 6

6x - 6y - 21x + 6y = 4

15x = 4

x = 4 /15


Putting in ( i )

3x - 3y = 5

3 × 4 /15 - 3y = 5

4/5 - 3y = 5

( 4 - 15y )/5 = 5

4 - 15y = 25

- 15 y = 21

y = - 21 /15

y = - 7 / 5