Answer:
Explanation:
5x + 3y = 45 ----------- ( 1 )
-7x + 3y = 81 ----------- ( 2 )
5x + 3y = 45 --------- ( 1 )
7x - 3y = - 81 --------- ( 3 )
Adding ( 1 ) & ( 3 ) ; we get ,
12x = - 36
x = - 3
putting value of x in equation ( 2 ) ; we get ,
21 + 3y = 81
3y = 60
y = 20