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

y= -3x + 7 -2x+6y=3

2 Answers

6 votes
6y = -x - 7
y= 6x - 3
__________________

y = x/6 + 7/6
y= 6x - 3

Compare the gradients, one is 1/6, one is 6. These are not parallel because they aren't the same, and not perpendicular because they aren't negative reciprocals. Therefore, neither.
User Siliconpi
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4 votes

Answer:

Perpendicular lines

Explanation:

We are given that


y=-3x+7


-2x+6y=3

We have to find the pair of equations are parallel , perpendicular or neither.

Differentiate each equation w.r.t.x


m_1=(dy)/(dx)=-3

Using rule :
(dx^n)/(dx)=nx^(n-1)


-2+6(dy)/(dx)=0


6(dy)/(dx)=2


m_2=(dy)/(dx)=(2)/(6)=(1)/(3)


m_2=-(1)/(m_1)=-(1)/(-3)=(1)/(3)

When two lines are perpendicular then ,


m_1=-(1)/(m_2)

When two lines are parallel then, slope of two lines are equal.

We have


m_2=-(1)/(m_1)=(1)/(3)

Hence, the lines are perpendicular.

User Matthijs Van Hest
by
8.3k points