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Which of the following pairs of slopes are of perpendicular lines?

1/2 and 2
3/4 and -4/3
-2/5 and -5/2

User Roman Vogt
by
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2 Answers

7 votes

Answer:

3/4 and -4/3

Explanation:

Out of all three, this would be the answer solely because -4/3 is the negative reciprocal of 3/4. -2/5 and -5/2 would be perpendicular if 2/5 was a positive value. 1/2 and 2 is definitely not perpendicular, either, due to the rule.

User LeeTee
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7.9k points
4 votes
perpendicular lines have negative reciprocal slopes.

To find the negative reciprocal of a number, u flip the number and change the sign.

Example : -3/1 and 1/3 are perpendicular...notice that if I flip -3/1 making it -1/3...and then change the sign....1/3...these are negative reciprocals.

1/2 and 2.....if u flip 1/2 making it 2/1...and change the sign...making it -2/1...therefore, these r NOT perpendicular...1/2 and -2 would be.

3/4 and -4/3.....flip and change sign...so 3/4 becomes - 4/3...these r perpendicular.

-2/5 and -5/2....flip and change...-2/5 becomes 5/2....these r NOT perpendicular...-2/5 and 5/2 would be.
User Sam Estep
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8.2k points