Question

Check my answers please? Really easy!

1. What is the solution of log4(2x 6)=2?

5
7
11 <---
14


2. What is the solution, or what are the solutions, of 2log6(x)=log6(100)?

10 only
-10 only
-10 and 10 <---
no solution


3. What is the solution, or what are the solutions, of log9(x^2)=log9(25)?

5 only
-5 only
-5 and 5 <---
no solution


4. What is the solution of log3(x + 7) + log3(3)=2?

-4 <---
5
10
no solution

Answer 1

I feel pretty confident about 1, 2 and 4, but I'm not sure if number 3 is correct. Can you help me out?