Answer:
3
Step-by-step explanation:
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction
3^4 +9^2÷3^3-9^2
81+81÷27-81
81+3-81
3
Answer:
see graph of y=3/4 x-4
Step-by-step explanation:
Assuming you mean

Below is a graph of that one. The slope is 3/4 and the interception with the y axis is at y=-4. The equation is in its normal form y=ax+b with a=3/4 (slope) and b=-4 (y intercept), so no conversion needed.
You have to be careful on how you write these equations down. It might very well be that you meant:
or 
However, those are more complex so I'm hoping for the first one... ;-)