WEBVTT
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What is the equation of the straight line that passes through the point one, two and that is parallel to the line π¦ equals negative five?
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So letβs have a look at this point one, two which would be here on the grid.
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We need to find the line which passes through this point and which is parallel to the line π¦ equals negative five.
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When we have a line like π¦ equals negative five, what weβre really saying is that the π¦-value must always be negative five and the π₯-value can be anything.
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For example, on this line, we could have one, negative five; three, negative five; or even negative two, negative five.
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The line which passes through all of these points with a π¦-value of negative five is in fact the line π¦ equals negative five.
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When weβre given the equation of a line that just has a π¦-variable, then this will give us a horizontal line.
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The line that weβre looking for that passes through the point one, two must also be a horizontal line.
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Itβs going to have just one variable in the equation which is going to be π¦, and the π¦-intercept will give us the constant term.
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So π¦ is equal to two.
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We can check this by remembering that this will mean that every π¦-value on this line would be two.
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So we could have the coordinate three, two on this line or five, two on this line or even negative four, two.
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In all of these cases, the π¦-value in each ordered pair will be two.
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So the answer then that the equation of the straight line passing through the point one, two and parallel to π¦ equals negative five is the line π¦ equals two.