Question

How can you determine if two lines, plotted on the x-y graph and represented as y=mx + b are perpendicular?

Answer 1

y = mx + b

In the above Eq, m is the slope and b is the y-int.
When 2 lines are perpendicular, their slopes are negative reciprocals of each other: y = (1/2)x + 7 and
y = -2x + 7. Two lines are per.
if their slopes are reciprocals AND
their signs are opposite. These 2 Eq
meet both requirements. Therefore,
they are perpendicular.

If you graphed these 2 lines, you notice that a right angle is formed
at the point of intersection.