Select the correct answer.

Are the given lines parallel, perpendicular, or neither?

[tex]\[
\begin{array}{l}
3x + 12y = 9 \\
2x - 8y = 4
\end{array}
\][/tex]

A. The slopes of the lines are not the same, so they are perpendicular.
B. The product of the slopes of the lines is 1, so the lines are perpendicular.
C. The slopes of the lines are opposites, so they are neither parallel nor perpendicular.
D. The quotient of the slopes of the lines is 1, so the lines are parallel.



Answer :

To determine whether the given lines are parallel, perpendicular, or neither, we first need to find the slopes of each line.

The given equations are:
1. [tex]\( 3x + 12y = 9 \)[/tex]
2. [tex]\( 2x - 8y = 4 \)[/tex]

First, we rearrange each equation into the slope-intercept form ([tex]\( y = mx + b \)[/tex]), where [tex]\( m \)[/tex] represents the slope:

### For the first equation:
[tex]\[ 3x + 12y = 9 \][/tex]

1. Isolate [tex]\( y \)[/tex]:
[tex]\[ 12y = -3x + 9 \][/tex]

2. Divide by 12 to solve for [tex]\( y \)[/tex]:
[tex]\[ y = -\frac{3}{12}x + \frac{9}{12} \][/tex]
[tex]\[ y = -\frac{1}{4}x + \frac{3}{4} \][/tex]

So, the slope ([tex]\( m_1 \)[/tex]) of the first line is:
[tex]\[ m_1 = -\frac{1}{4} \][/tex]

### For the second equation:
[tex]\[ 2x - 8y = 4 \][/tex]

1. Isolate [tex]\( y \)[/tex]:
[tex]\[ -8y = -2x + 4 \][/tex]

2. Divide by -8 to solve for [tex]\( y \)[/tex]:
[tex]\[ y = \frac{2}{8}x - \frac{4}{8} \][/tex]
[tex]\[ y = \frac{1}{4}x - \frac{1}{2} \][/tex]

So, the slope ([tex]\( m_2 \)[/tex]) of the second line is:
[tex]\[ m_2 = \frac{1}{4} \][/tex]

Now that we have the slopes:
- Slope of the first line, [tex]\( m_1 = -\frac{1}{4} \)[/tex]
- Slope of the second line, [tex]\( m_2 = \frac{1}{4} \)[/tex]

Next, let's determine the relationship between the two lines:

1. Parallel: Lines are parallel if their slopes are equal.
- [tex]\( m_1 \neq m_2 \)[/tex] so the lines are not parallel.

2. Perpendicular: Lines are perpendicular if the product of their slopes is -1.
- [tex]\( m_1 \times m_2 = -\frac{1}{4} \times \frac{1}{4} = -\frac{1}{16} \neq -1 \)[/tex] so the lines are not perpendicular.

3. Neither: Since the slopes are not equal and their product is not -1, the lines are neither parallel nor perpendicular.

Therefore, the correct answer is: the lines are neither parallel nor perpendicular.