2/7(4 2/3m-1,4)-2/9(6m+2,7)
2/7(4 2/3m - 1.4) - 2/9(6m+2.7)=2/7 * 14/3 m - 2/7 * 7/5 - 2/9 * 6 m - 2/9*27/10=4/3m - 2/5 - 4/3 m - 3/5= - 5/5= - 1