题目内容
已知直线l1:x+my+6=0,l2:(m-2)x+3y+2m=0,分别求m的值,使得:
(1)l1⊥l2;
(2)l1∥l2.
(1)l1⊥l2;
(2)l1∥l2.
(1)∵直线l1:x+my+6=0,l2:(m-2)x+3y+2m=0,由l1⊥l2 ,可得 1×(m-2)+m×3=0,解得m=
(2)由l1∥l2 可得
=
≠
解得:m=-1
| 1 |
| 2 |
(2)由l1∥l2 可得
| m-2 |
| 1 |
| 3 |
| m |
| 2m |
| 8 |
解得:m=-1
练习册系列答案
相关题目