Summer has rolled around, but my studying continues. I want to be prepared for Calculus next year, so I bought some textbook at a thrift store. Already I'm running into problems! The book tells me to find the distance between P and L. P is a coordinate pair and L is a line equation. I have done three of these problems and all three have ended up being wrong, though I don't know where exactly I have made a mistake in my math.(adsbygoogle = window.adsbygoogle || []).push({});

[tex]P(-2,2)[/tex] [tex]L:2x+y=4[/tex]

I get the points for L by making x=0 and y=0, and I end up with:

[tex]P(-2,2)[/tex] [tex]L(2,4)[/tex]

Then I use the distance formula:

[tex]\sqrt{(2+2)^2+(4-2)^2}[/tex] which ultimately becomes [tex]\sqrt{20}[/tex], and finally [tex]2\sqrt{5}[/tex]

Unfortunately for me, my book reads: [tex]6\sqrt{5}[/tex]

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# Homework Help: Having Trouble Finding the Distance

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