You can put this solution on YOUR website! graph the equation F(x)=18-x using slope intercept form
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Form: f(x) = -x + 18
slope is -1
intercept is 18
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Put a point at (0,18), the y-intercept.
Slope tell you "as x increases by 1, y decreases by 1".
Put a point at (1,17)
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Draw a line thru those two points; that is your graph.
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Cheers,
Stan H.