请大家用代如消元法解下列方程组:(1)9s-13t+12=0 (2)x/4+y/3=4/3 s=2-3t 3(x-1)=4(y+2_数学解答

请大家用代如消元法解下列方程组:
(1)9s-13t+12=0 (2)x/4+y/3=4/3
s=2-3t 3(x-1)=4(y+2)
1)9s-13t+12=0 s=2-3t (2)x/4+y/3=4/3 3(x-1)=4(y+2)
格式错了应该是现在这样

人气：262 ℃　时间：2020-05-13 02:14:55

解答

9s-13t+12=0,s=2-3t,用S代入得9(2-3t)-13t+12=0→18-27t-13t+12=0→30=40t→t=3/4
x/4+y/3=4/3→3x+4y=16→y=4-16/3x代入3(x-1)=4(y+2)得x=27/19y=-68/19