The first one and the third one are correct. because for the when you plug 1 on the first piece wise function you get 3.
f(3) =1. and f(1)=3 so f(1)>f(3)
when you have a linear combination for example 3x + 2y equals negative 4 you adieu like terms and then multiply
The answer is 8 and yea it’s 2 steps first u have to remove the constant so u subtract 74-2=72 and 2-2=0. After u get rid of the constant u divide both sides by 9 basically 72/9 and 9/9 which is 8. So n is equal to 8 I hope this helped. I know it can be confusing