Question

$3a - 7 = 12 + 4a$

Answer 1

3a -7 = 12 + 4a
=> 3a-4a = 12+7
=> -a = 19
=> a = -19




HOPE IT HELPS YOU !!!

Answer 2

3a - 7 = 12 + 4a


Transport the same variable on the same side and constant terms on same side. While transporting, the symbols will change, that is:-
+ changes to -
- changes to +
× changes to ÷
÷ changes to ×

Now,

3a - 7 = 12 + 4a

Transport 3a to RHS (right hand side) and 12 to LHS (left hand side)

Since 12 and 3a both are +ve They will change to - after transport

=> -12 - 7 = 4a - 3a

=> -19 = a

=> a = - 19

Hope it helps dear friend ☺️✌️