Answer:
tu debes de saber por qué si yo lo sé tú también no es verdad
Answer:
C: 
Step-by-step explanation:

Since a =
:

Since n = 4 :

Answer:
6/8
Step-by-step explanation:
3/8 + 3/8 = 6/8
Hope this helps :D
Answer:
x=9
Step-by-step explanation:
Using elimination method.
Add equation 1 to equation 2
x + y = 11
x - y = 7
---------------
2x + 0 = 18
Divide both sides by 2
2x = 18
---- ----
2 2
x = 9