You can put this solution on YOUR website! Here's the graphs:
You can see the line with negative slope goes through
( -6, 0 ) and
( 0, -8 )
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The line with positive slope goes through
( 1, 0 ) and
( 0, -1 )
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All you need is 2 points to plot a line, so you are done
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Here's how to get ( -6, 0 )
Let
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Just follow this method