Answered

Which statement explains how the lines [tex]2x + y = 4[/tex] and [tex]y = \frac{1}{2}x + 4[/tex] are related?

A. They are parallel.
B. They are perpendicular.
C. They are the same line.
D. They are not related.



Answer :

To determine the relationship between the lines given by the equations [tex]\(2x + y = 4\)[/tex] and [tex]\(y = \frac{1}{2}x + 4\)[/tex], we follow these steps:

1. Convert the first equation to slope-intercept form: The equation of a line in the slope-intercept form is [tex]\( y = mx + b \)[/tex], where [tex]\(m\)[/tex] is the slope and [tex]\(b\)[/tex] is the y-intercept.

Given the equation [tex]\(2x + y = 4\)[/tex], we solve for [tex]\(y\)[/tex]:
[tex]\[ y = -2x + 4 \][/tex]

Therefore, the slope [tex]\(m_1\)[/tex] of the first line is [tex]\(-2\)[/tex].

2. Identify the slope of the second line: The second line is already in slope-intercept form [tex]\( y = \frac{1}{2}x + 4 \)[/tex].

So, the slope [tex]\(m_2\)[/tex] of the second line is [tex]\(\frac{1}{2}\)[/tex].

3. Compare the slopes to determine the relationship:
- Two lines are parallel if their slopes are equal.
- Two lines are perpendicular if the product of their slopes is [tex]\(-1\)[/tex], i.e., [tex]\(m_1 \times m_2 = -1\)[/tex].
- If neither of these conditions is met, then the lines are either the same line or not related.

In this case, the slopes are:
[tex]\[ m_1 = -2, \quad m_2 = \frac{1}{2} \][/tex]

To check if they are perpendicular:
[tex]\[ m_1 \times m_2 = -2 \times \frac{1}{2} = -1 \][/tex]

Since the product of the slopes is [tex]\(-1\)[/tex], the lines are perpendicular.

Therefore, the lines [tex]\(2x + y = 4\)[/tex] and [tex]\(y = \frac{1}{2}x + 4\)[/tex] are perpendicular. The correct statement is:

They are perpendicular.