A-5/12a=1/4 Плз решите

Question

A-5/12a=1/4
Плз решите

Answer 1

А - ( 5/12 ) А = 1/4
( 12/12 ) А - ( 5/12 ) А = 1/4
( 7/12 ) А = 1/4
А = ( 1/4 ) : ( 7/12 )
А = ( 1/4 ) * ( 12/7 )
А = 3/7

Answer 2

А-5/12а=1/4. ×12
12(а-5/12а)=12×1/4
12а-5а=3
7а=3
а=3/7