Basics of Straight line - 2D (for HSC / JEE / CET and other entrance exams)

General equation of line,
Slope of a line,
Equation of line in slope intercept form,
Equation of line in slope point form,
Equation of line in two point form,
Equation of line in double intercept form,
Distance between two parallel lines,
Distance of a point from the line,
Foot of the perpendicular,
Reflection of the point,
Angle between the lines,
Condition for concurrency

[@xiaoming2799]

Keep up the good work!