∴可设直线l的方程为y+5=k•(x-2),
即kx-y-2k-5=0.
∴A(3,-2)到直线l的距离为d1=
|3k+2−2k−5| | ||
|
|k−3| | ||
|
B(-1,6)到直线l的距离为d2=
|k•(−1)−6−2k−5| | ||
|
|3k+11| | ||
|
∵d1:d2=1:2
∴
|k−3| |
|3k+11| |
1 |
2 |
∴k2+18k+17=0.
解得k1=-1,k2=-17.
∴所求直线方程为x+y+3=0和17x+y-29=0.
|3k+2−2k−5| | ||
|
|k−3| | ||
|
|k•(−1)−6−2k−5| | ||
|
|3k+11| | ||
|
|k−3| |
|3k+11| |
1 |
2 |