First you combine like terms. Adding 5n and 4n together to get 9n+3=30. Then you subtract 3 from 30 and end up with 9n=27.
Then you divide 27 by 9 and end up with n=3.
So the answer is 3.
just subtracting by 2x on both sides
hope this helps
Answer:
10
Step-by-step explanation:
The current probability of picking a red ball is
. When 5 more balls are added, the probability is 3/4. We can write a ratio for this problem:

When using cross multiplication to solve this, you get 3 * 20 = 4(x+5).
60 = 4x + 20
40 = 4x
x = 10 red balls