If the line is parallel to the given line x-2y + 5 =0,
then the required line will have same slope
Hence the equaion of the given line is x-2y+k=0
since it passes through the origin,
0+0+k=0
Therefore k=0
Hence the equation of the required line is x-2y=0 or x=2y
distributive law
since
since


is a circle. The points (0, 0) and ( 1, 8) lie

units which is less than the radius so it lies inside the circle
which is greater than the radius so it lies outside the circle