Guys i really need an answer it is due tommorow i really need

What is the value of  y  in the solution to the system of equations? x  +  y  =  12x  –  3y  =  –30a. –8b. –3c. 3d. 8

Diane owes $387 to her brother. if she debits her bank account $161.25 a month to pay him back, how many months will it take her to pay off the debt?

Write the fraction or mixed number and the decimal shown by the model