the lines are perpendicular when the gradient of the first line multiplied by the gradient of the second line gives you -1
Hi folks, yr 10 student dilemna here!
need to know this 4 test tomoro, just some pointers for finding the equations of straight lines which pass through a given point and perpendicular to the line whose equation is given by:...... and so on,, same with parallel.
how to show that lines are perpendicular, with 2 equations???
any help welcome,
thanks a lot!
The general equation of a straight line is:
Two lines are parallel if they have the same direction (=slope, gradient):
... and ...
Two lines are perpendicular if
If you have the slope (=direction) of a straight line and a point which is placed on this line (or the line passes through the point P) then the coordinates of P must satisfy the equation:
... This is the point-slope-formula of a straight line.