问题
解答题
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.
答案
(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=1 2
(2)由l1∥l2 可得
=m-2 1
≠3 m 2m 8
解得:m=-1
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)∵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=1 2
(2)由l1∥l2 可得
=m-2 1
≠3 m 2m 8
解得:m=-1