Respuesta :

3 because 6x3 +2 =20 and -3+23=20

Answer:

AC=20

Step-by-step explanation:

6y+2 = -y+23

move y to one side

7y+2=23

move 2 to the other side

7y=21

divide by 7 on both sides to isolate y

y=3

Substitute y in

-3+23=20

Check your work,18+2=20