For question 3, the answer is f(x)=3x-4.
In question 3, if -7 is f(x), and it is 3x-4, the answer is -1; if -7 is f(x), and the answer is 4x-3, the answer is -1; if -7 is f(x), and it is 1/2x+3, answer is -20; if -7 is f(x), and it is 3x+1/2, the answer is -5/2.
But, if -4 is f(x), and it is 3x-4, the answer is 0; if -4 is f(x), and it is 4x-3, the answer is -1/4.
So f(x)=3x-4 is the answer for question 3.
For question 4, the answer is the last choice.
Like the one above 3x was the rate and -4 is the initial value.
So for this one, 2/3 is the rate and -2 is the initial value.
