Slope is rise/run or y2-y1/x2-x1. So to find the slope, find two points where the point is exact, then do the equation. That's the best I can explain, sorry if this doesn't help at all.
Answer:
x=21
Step-by-step explanation:
subtract 6 from both sides get -1/3x=-7
multiply -1/3 or -1/3 as decimal times -7
and get x=21
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