Respuesta :

4x + 12= 20
 4x= 20-12
4x= 8
x= 8/4 = 2
     
4(x+3)=20
multiply 4 time x and 4 time 3 
4x+12=20
then you subtract 12 to 20 and is 8
4x=8 
then you divide 8 by 4 and i 
x=2