已知兩條直線l1:x+m2y+6=0,l2:(m-2)x+3my+2m=0,當m為何值時,l1與l2(1)相交...
問題詳情:已知兩條直線l1:x+m2y+6=0,l2:(m-2)x+3my+2m=0,當m為何值時,l1與l2(1)相交;(2)平行;(3)重合.【回答】【解】當m=0時,l1:x+6=0,l2:x=0,∴l1∥l2.當m=2時,l1:x+4y+6=0,l2:3y+2=0,∴l1與l2相交.當m≠0且m≠2時,由,得m=-1或m=3,由,得m=3.故(1)當m≠-1且m≠3且m...