15, 30, 45, 60, 75, 90, ....
To find if something is a parallelogram, they 1 set of line segments need to have the the slope. In this equation, Slope equals x1 + x2 divided by y1 + y2 (Or the other way around, x2 + x1 divided by y2 + y1)

For your other point, it could be (-4,5)
If this is confusing, please tell me! I'll try to better explain. It also helps to draw out a graph so you can plot the points.
Answer:
D because it’s D give me brainless
Step-by-step explanation:
3t-1=8
3t=8+1
3t=9
3t divide by 9
Will give you 3
So your t value would be 3
Explanation: you would have to bring the -1 over to the 8, making the 1 positive. Then you would add up 8 nd 1.
And just divide the two numbers so 9 divide by 3. And you would have your answer T=
Hope this helped
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