Respuesta :
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 ! ^-^

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 ! ^-^