9. Find the distance from point P (-5,7) to line 12x+5y-3=0.
10. Find the distance between two parallel straight lines 3x-2y- 1=0 and 3x-2y+ 1=0.
Group b: 1. Three straight lines ax+2y+8=0 and 4x+3y= 10 and 2x-y= 10 intersect at one point to find the value of a.
4. Given that the distances from point A (-3, -4) and point B (6, 3) to the straight line L are equal: AX+Y+ 1 = 0, find the value of a..
5. Find a point P on the X axis, so that the triangle area with points A( 1 2), B (3,4) and P as vertices is 10.
9. It is known that the linear equation of the center line CM at the vertex A and AB of △ABC (5, 1) is 2x-y-5=0, and the linear equation of the height BH at the AC side is x-2y-5=0. Find the coordinates of vertex c (1); (2) Linear equation BC