Respuesta :

emanuelmendoza577

Answer:

X = 6

Step-by-step explanation:

meadowsbianca19

Answer:

b. 6

Step-by-step explanation:

2x + 9 = 21

then you subtract 9 from each side

2x = 12

then you divide 2 from each side

x = 6

Hope this helps dude ! ^-^