Respuesta :

Answer:

See explanation

Step-by-step explanation:

3x/(-8)=-21/4

-3x/8=-21*8/4

-3x*8/8=-21*8/4    ==> multiply 8 on both sides to get rid of denominator

-3x=-21*2

-3x=-42

3x=42   ==> Multiply by -1 on both sides to get positive values on both sides

x=14