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
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
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
-------------
Your lines are
(1)
(2)
--------------
(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,
