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Prealgebra- Determine whether the lines passing through the pairs of points are parallel, perpendicular, or neither

Prealgebra- Determine whether the lines passing through the pairs of points are parallel-example-1
User Mehr
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1 Answer

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It is important to note the following:

• If the slopes of the two lines are equal, they are parallel.

,

• If the slopes of the two lines are negative reciprocal of each other, they are perpendicular.

Let's now calculate the slope of each line. Use the formula:


m=(y_2-y_1)/(x_2-x_1)

Let's start with line 1.


m=(1-13)/(-8-1)\Rightarrow m=(-12)/(-9)\Rightarrow m=(4)/(3)

The slope of line 1 is 4/3.

Let's move on to line 2.


m=((5)/(3)-(-1))/(5-3)\Rightarrow m=((8)/(3))/(2)\Rightarrow m=(4)/(3)

The slope of line 2 is also 4/3.

Since the slopes of the two lines are the same, then the two lines are parallel.

User Blueyed
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