3) To find an angle, we should find slope
for AB line and slope for CD line.
If we will choose equation of line AB as so, we will have a system: From it, we could find that
Like that, CD line has equation and .
As it means that, these lines are perpendicular. The answer: AB and CD are perpendicular.
4) As the question above, we could find that . As, , AB and CD lines have equal slopes, more clearly, they are parallel lines. Answer: AB and CD lines are parallel
Comments