## anonymous 4 years ago Show that a line through (0, 0) and (c, d) is perpendicular to a line through (0, 0) and (-d, c). Slope of first line = Slope of second line =

1. ash2326

johny find the slope of both the lines , let them be m1 and m2 if $m1*m2=-1$ then the lines are perpendicular

2. anonymous

Two lines are perpendicular if the product of there slopes is -1

3. anonymous

For the line through (0, 0) and (c, d) the slope is $$\frac {d}{c}$$ and for the line through (0,0) and (-d.c) the slope is $$-\frac{c}{d}$$ now if you take the product it will be -1 hence the two lines will be perpendicular.