Respuesta :

Answer:

c = -7

Step-by-step explanation:

3c + 21 = 4c + 28

21 = c + 28

-7 = c

Answer:

c= -7

Step-by-step explanation:

Subtract 3c from both sides

21+3c=4c+28

21=c+28

Subtract 28 from both sides

c= -7

Hope this helps! :)