Supplementary means it adds up to 180 degrees.
So if one side is 31 degrees, you would need to subtract that from 180 to find the other side.
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180 - 31 = 149
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The other angle would be 149 degrees.
Yes the graph does show a proportional relationship because each x value has only one y value
Answer:
The the equation written in slope-intercept form from the two given points should be
.