Hi,
Determine whether each pair of equations represents perpendicular lines.
y=5-3x, 3x-y=8
y = mx + b
y = -3x + 5 m = -3
& y = 3x - 8 m = 3
NO, this pair of equations do not represent perpendicular lines
Answer by tutor_paul(519) (Show Source): You can put this solution on YOUR website! You can determine if two lines are perpendicular by finding their slopes. The rule is that 2 lines are perpendicular if their slopes are negative reciprocals of each other. So first, re-write the given equations in y=mx+b form so you can easily find the slope (m).
Equation #1:
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The slope of this line is thus -3
Equation #2:
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The slope of this line is thus +3
-3 and 3 are NOT negative reciprocals of each other, so these 2 lines are NOT perpendicular.
Note: if you are not sure what negative reciprocal means, slopes such as -3 and 1/3 are negative reciprocals.
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Good Luck,
tutor_paul@yahoo.com
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website! If you have a line that looks like , then a line perpendicular to it
looks like where is slope
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Your lines are
(1)
(2)
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(1)
and
(2)
Multiply both sides by
(2)
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Now compare the slopes. They are
and
They can't be perpendicular because and to be perpendicular,