SOLUTION: If the slope of the line determined by the points (x,5) and (2,8) is -3, find x?

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Question 1079739: If the slope of the line determined by the points (x,5) and (2,8) is -3, find x?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
( x,5 ), ( 2,8 )
The slope is [ change in y ] / [ change in x ]
+%28+8+-+5+%29+%2F+%28+2+-+x+%29+=+-3+
+3+%2F+%28+2+-+x+%29+=+-3+
Multiply both sides by +2-x+
+3+=+-3%2A%28+2+-+x+%29+
+3+=+-6+%2B+3x+
+3x+=+3+%2B+6+
+3x+=+9+
+x+=+3+
----------------
check answer:
+%28+8+-+5+%29+%2F+%28+2+-+x+%29+=+-3+
+%28+8+-+5+%29+%2F+%28+2+-+3+%29+=+-3+
+3+%2F+%28-1%29+=+-3+
+3+=+%28-1%29%2A%28-3%29+
+3+=+3+
OK