Your answer is 1 and 7/8.
Multiply 3.3 by everything in the parenthesis.
3.3x - 26.4 - x = 1.2
Combine like terms.
2.3x - 26.4 = 1.2
Add 26.4 to both sides.
2.3x = 27.6
Divide 2.3 on both sides.
x = 12
Hope this helps!
Your're lucky am going to help. Kidding. :D
All real numbers but 3 and -3
They are inverse functions though to be completely thorough your teacher should have also put g(f(x)) = x as well. Though I can see what your teacher is aiming for at least.
The idea is that whatever the output of g(x) is, it's plugged into f(x) and the initial input is the result. So g(x) takes a step forward and f(x) takes a step back undoing everything g(x) did. Which is exactly what an inverse operation does.
The fraction is written as 3/4.
If you divide 3 by 4 you will get the decimal.