Respuesta :

Answer:   " y = 21 " .
____________________________________________
Cross multiply:
______________________________

(2y)(4) = 7(y + 3) ;

     8y = 7y + 21

Subtract 7y from each side of the equation;

    8y - 7y = 7y + 21 - 7y  ;

           y = 21 .
_____________________________________