SOLUTION: find an equation of the line through (8,-4) and parallel to 8x+5y=2

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Question 581572: find an equation of the line through (8,-4) and parallel to 8x+5y=2
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
First find the slope of the equation by
putting it in the form +y+=+mx+%2B+b+
where m = slope
+8x+%2B+5y+=+2+
+5y+=+-8x+%2B+2+
+y+=+-%288%2F5%29%2Ax+%2B+2%2F5+
The slope is +-%288%2F5%29+
Any line parallel to this line will also
have slope = +-%288%2F5%29+
------------------
(8,-4)
Use the point-slope formula
+%28+y+-+%28-4%29+%29+%2F+%28+x+-+8+%29+=+-%288%2F5%29+
Multiply both sides by +5%2A%28+x-8+%29+
+5%2A%28+y+%2B+4+%29+=+%28-8%29%2A%28+x+-+8+%29+
+5y+%2B+20+=+-8x+%2B+64+
+8x+%2B+5y+=+-20+%2B+64+
+8x+%2B+5y+=+44+
--------------
Check:
what is the slope?
+8x+%2B+5y+=+44+
+5y+=+-8x+%2B+44+
+y+=+-%288%2F5%29%2Ax+%2B+44%2F5+
slope is +-%288%2F5%29+
does it go through (8,-4) ?
+8x+%2B+5y+=+44+
+8%2A8+%2B+5%2A%28-4%29+=+44+
+64+-+20+=+44+
+44=+44+
OK