(3x + 20)*(2x + 9) - (x + 2)*(6x + 1) = (x + 1) - (x - 6)

a) (3x+20)*(2x+9)-(x+2)*(6x+1)=(x+1)-(x-6)
b) 3*(2x-1)*(3x-1)-(2x-3)*(9x-1)=0