Line Equation

Line A y = 2x - 3
Line B y = 2x + 5
Line C y = -1/2x - 2
Line D y = 1/2x + 2

Given the linear equation in the table, which of the following statements is true?

a. Line A is perpendicular to line B
b. Line C is perpendicular to line D
c. Line A is perpendicular to line C
d. Line B is perpendicular to line D

1 answer

To determine which statements about the lines are true, we need to check the slopes of the lines involved. Two lines are perpendicular if the product of their slopes is -1.

Here are the slopes of the given lines from their equations:

  • Line A: \( y = 2x - 3 \) (slope = 2)
  • Line B: \( y = 2x + 5 \) (slope = 2)
  • Line C: \( y = -\frac{1}{2}x - 2 \) (slope = -\frac{1}{2})
  • Line D: \( y = \frac{1}{2}x + 2 \) (slope = \frac{1}{2})

Now, we can evaluate each statement:

a. Line A is perpendicular to line B.

  • False, since both lines have the same slope (2).

b. Line C is perpendicular to line D.

  • Evaluate the product of their slopes: \(-\frac{1}{2} \times \frac{1}{2} = -\frac{1}{4}\).
  • False, since the product is not -1.

c. Line A is perpendicular to line C.

  • Evaluate the product of their slopes: \(2 \times -\frac{1}{2} = -1\).
  • True, since the product is -1.

d. Line B is perpendicular to line D.

  • Evaluate the product of their slopes: \(2 \times \frac{1}{2} = 1\).
  • False, since the product is not -1.

Thus, the only true statement is:

c. Line A is perpendicular to line C.