You can put this solution on YOUR website! The formula for slope-intercept is :
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y=mx+b
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so, they gave you 3y+x-9=0
so make it look like the slope intercept form by getting Y on one side of the equal sign.
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In order to do that you need to subtract x and add 9 to both sides:
3y+x-9=0
-x+9=-x+9
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3y=-x+9 ...but the Y must be by itself so divide both side by 3:
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y= -1/3x+3...(final answer)
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so that is how to put it into slope intercept form.
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