SOLUTION: How can you determine if two lines are perpendicular?

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Question 133953: How can you determine if two lines are perpendicular?
Found 2 solutions by jojo14344, solver91311:
Answer by jojo14344(1513) About Me  (Show Source):
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If two lines meet and form 90 degree angle, then they are perpendicular.

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
If you are given the equations of the lines, solve the equations for y in terms of x -- in other words put them into slope-intercept form, y=mx%2Bb. Then compare the slopes of the two lines. Two lines are perpendicular if and only if their slopes are negative reciprocals of each other. That is to say if m%5B1%5D is the slope of one of the lines and m%5B2%5D is the slope of the other line, the lines are perpendicular if and only if m%5B1%5D=-%281%2Fm%5B2%5D%29.