[填空题]
The coordinates of point A are (−1,−7) and the cox*5x982- 8bitk vl;ns *kdzqn z kzvo6o 5 5 */grcrptobbu:2ta-s dh)brdinates of point B are (5,2). d /rorsp: 2-babt55 ugtb) *ch$L_1$ is the line which passes through A and B.
1.Find the equation of $L_1$.
Point M is the midpoint of [AB]. The line $L_2$ is perpendicular to $L_1$ and passes through M. y = ax+b a= b =
2.Find the equation of $L_2$. y = ax+b a= b =
