Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation : 
 y-(12*x^2-9*x+4)=0 
Step by step solution :
Step 1 :Equation at the end of step 1 : y - (((22•3x2) - 9x) + 4) = 0 Step 2 :Equation at the end of step 2 : y - 12x2 + 9x - 4 = 0 Step 3 :Solving a Single Variable Equation : 3.1  Solve  y-12x2+9x-4  = 0 
In this type of equations, having more than one variable (unknown), you have to specify for which variable you want the equation solved.