t1 = Z1^2 t2 = X1 - t1 t1 = t1 + X1 t3 = t1 * t2 t1 = t3 + t3 t1 = t1 + t3 t3 = Y1^2 t3 = t3 + t3 t2 = X1 * t3 t2 = t2 + t2 X = t1^2 X = X - t2 X3 = X - t2 t4 = Y1 * Z1 Z3 = t4 + t4 t2 = t2 - X3 Y = t1 * t2 t4 = t3^2 Y = Y - t4 Y3 = Y - t4