Assume that X=Y

X=Y

XX=XY-----------------Multiply bothe sides by X.

X^2-Y^2=XY-Y^2-----Subtract Y^2 from both sides.

(X+Y)(X-Y)=Y(X-Y)----Factor the terms.

X+Y=Y-----------------Cross out like terms.

Y+Y=Y--------------Substitute Y for X-See step one.

2Y=Y---------------Because Y+Y=2Y.

2x1=1--------------Divide both sides by Y.

2=1----------------Solve.