how do i write equation of vertical line which goes through (-3,18)?

Question

ybarrap · Answer

@cialos123 Welcome to Open Study!

ybarrap · Answer

So we want a vertical line, that means we want some x value that goes through <-3,18>

If we set x = -3, then it goes through all x values, including y=18.

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ybarrap · Answer

*If we set x = -3, then it goes through all y values, including y=18.

ybarrap · Answer

That's it, that's our equation: x=-3.

anonymous · Answer

could you show me how you arrived at that answer?
.

ybarrap · Answer

Yes.

You want a vertical line, so that means it will be parallel to the y-axis

If a line is parallel to the y-axis it goes through all points on the y-axis.

Does this make sense so far?

anonymous · Answer

yes

ybarrap · Answer

Ok. 

So whichever line we choose that is parallel to the y-axis must also go through y=18 because lines parallel to the y-axis go through all points on the y-axis.

The reason I am talking about y=18 is because we are looking for a specific line. One that goes through the point <-3,18>, which means x = -3  the value of y = 18, this is just a point in the x-y plane:

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Does this make sense?

ybarrap · Answer

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