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Determine whether the lines are parallel, intersect, or coincidingY= 1/3x + 4X - 3y = -12

User Meeeee
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1 Answer

19 votes
19 votes

So, we want to determine whether the lines:


\begin{gathered} y=(1)/(3)x+4 \\ x-3y=-12 \end{gathered}

First, remember that there are two different ways to represent a line with an equation. These are:


y=mx+b

Where m is the slope.

For example:


y=(1)/(3)x+4

Where the slope is 1/3.

The second way, has the equation of the form:


Ax+By+C=0

Where the slope is given by the operation:


(-A)/(B)

For example:


x-3y+12=0

Where the slope is:


(-(1))/(-3)=(1)/(3)

As you can see, both lines has the same slope, so, they are parallel.

Remember!

- Two lines are parallel if they have the same slope.

- Two lines are perpendicular if the product of their slopes is -1.

User Squirrelsareduck
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