Math madness

Something here doesn't add up

                a = b
            a^2 = ab
        a^2-b^2 = ab-b^2
     (a+b)(a-b) = b(a-b)
            a+b = b
             2b = b
              2 = 1


              x = (Pi+3)/2
             2x = Pi+3
       2x(Pi-3) = (Pi+3)(Pi-3)
        2Pix-6x = Pi^2-9
           9-6x = Pi^2-2Pix
       9-6x+x^2 = Pi^2-2Pix+x^2
        (3-x)^2 = (Pi-x)^2
            3-x = Pi-x
             Pi = 3  


             -1 = -1
           -1/1 = -1/1
           -1/1 = 1/-1
     sqrt(-1/1) = sqrt(1/-1)
            i/1 = 1/i
              i = 1/i
          i * i = 1
             -1 = 1

It took me a little bit to find the flaws in all of these. After that it's obvious why it's wrong, but until then, these things will make your head hurt.