Condition for the parallelism of two lines.

Condition for the parallelism of the lines

What is the condition for parallelism of two vectors ?

Derive the condition for the coplanarity of two lines in space both in vector and cartesian form.

Condition for Perpendicularity of two lines.

Write the condition for the pair of linear equations in two variables to be parallel lines.

Condition of coplanarity of two lines and equation of the plane containing them

The condition that the pair of straight lines ax^(2)+2xy+by^(2)=0 are parallel is:

If a line is divided by three parallel lines into two segments of lengths in the ratio 1 : 3 another line will be divided by these parallel lines into two segments of lengths in the ratio .............. .

Find the equation of the family of lines satisfying the following condition : parallel to the line 3x + 4y + 5=0.

The condition for collinearity for the two parallel lines vec(r)=vec(a)+tvec(b)" and " vec(r)=vec(a)_(1)+svec(b) is