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Tell us whether the lines for each pair of equations are parallel, perpendicular, or neither:

y=-4x +3; -2x+8y=5

User Leopectus
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2 Answers

4 votes

Answer:

Explanation:

perpendicularrrrrrrrrrrr....

User K To The Z
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4 votes
Two lines are parallel if the gradient (i.e. the x coefficient) of them both is the same.
Two lines are perpendicular if the gradient has its sign changed and has it's fraction flipped (i.e. a gradient of 2/3 would become -3/2, and a gradient of 10 would become -1/10)

THe first one is in the correct form already, with a gradient of -4.
Now we need to rearrange the second:
-2x+8y=5 \\ 8y=2x+5 \\ y= (2)/(8) x+ (5)/(8) = (1)/(4)x+ (5)/(8)
The second equation has a gradient of 1/4, which is indeed the negative and reversal of -4, therefore the two lines are perpendicular.

User Nick Brunt
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