Are the pairs of lines parallel, perpendicular, or intersecting?(3 points)

y−6=14(x+2)
y=−4x−10

2x−y=7
3x−4y=−8

y=−23x+7
−2x−3y=12
answers
parellel, perpendiculer, intersecting

1 answer

To determine whether the pairs of lines are parallel, perpendicular, or intersecting, we can convert the equations into the slope-intercept form \(y = mx + b\) where \(m\) is the slope.

Pair 1

  1. First Line:
    \(y - 6 = 14(x + 2)\)
    Expand:
    \(y - 6 = 14x + 28\)
    Therefore,
    \(y = 14x + 34\)
    Slope: \(m_1 = 14\)

  2. Second Line:
    \(y = -4x - 10\)
    Slope: \(m_2 = -4\)

Analysis of Pair 1

  • The slopes are \(m_1 = 14\) and \(m_2 = -4\).
  • Since the product of the slopes \(m_1 \cdot m_2 = 14 \cdot (-4) = -56\), which is negative, the lines are perpendicular.

Pair 2

  1. First Line:
    \(2x - y = 7\)
    Rearranging gives:
    \(y = 2x - 7\)
    Slope: \(m_1 = 2\)

  2. Second Line:
    \(3x - 4y = -8\)
    Rearranging gives:
    \(4y = 3x + 8 \implies y = \frac{3}{4}x + 2\)
    Slope: \(m_2 = \frac{3}{4}\)

Analysis of Pair 2

  • The slopes are \(m_1 = 2\) and \(m_2 = \frac{3}{4}\).
  • Since the product of the slopes \(m_1 \cdot m_2 = 2 \cdot \frac{3}{4} = \frac{3}{2}\), which is positive, the lines are intersecting.

Pair 3

  1. First Line:
    \(y = -23x + 7\)
    Slope: \(m_1 = -23\)

  2. Second Line:
    \(-2x - 3y = 12\)
    Rearranging gives:
    \(-3y = 2x + 12 \implies y = -\frac{2}{3}x - 4\)
    Slope: \(m_2 = -\frac{2}{3}\)

Analysis of Pair 3

  • The slopes are \(m_1 = -23\) and \(m_2 = -\frac{2}{3}\).
  • Since the slopes have the same sign and are not equal (not parallel), the lines are intersecting.

Summary of the results:

  • Pair 1: Perpendicular
  • Pair 2: Intersecting
  • Pair 3: Intersecting