Well, on the left hand side, these cancel out. And we're left with 2y minus 2x dy dx minus 1 dy dx. Or just minus a dy dx. Let me make it clear. We could write this as a minus 1 dy dx. So we can essentially just add these two coefficients. So this simplifies to 2y minus 2x minus 1 times the derivative of y with respect to x, which is going to be equal to, on this side, this cancels out.