Answer:
slope of st is -0.25
slope of tu is 1
slope of us is -0.25
slope of sv is 1 so it is a parallelogram. the slope of the parallel lines needs to be the same to be a parallelogram. to find the slope, you need to find the change from the points of the referenced line, for example, slope of st you would label each point as x1, y1 and x2,y2. it does not matter which one you label and you can change them for each different line. you would then find the difference by subtracting (y2-y1) divided by (x2-x1) so 4-3=1 and 1-5 is -4. you then divide 1/-4 is -0.25. you the follow the steps for each line. is the parallel lines have the same slope, it is a parallelogram