2u/3+3v/4=1/2 (1) 4u/5+5v/6=7/15 (2) (1) 两边同乘以12,化简得8u+9v=6 (3) (2) 两边同乘以30,化简得24u+25v=14 (4) (3)*3-(4)得,2v=4,即v=2 将v=2代入（3）得u=-3/2