Options A and D are the ones that would help show that quadrilateral LMNP is a parallelogram.
To show that quadrilateral LMNP on the coordinate plane is a parallelogram, you can use the following criteria:
A. Show that midpoint of LN is the same as midpoint of MP.
This is a property of parallelograms. If the midpoints of one pair of opposite sides are the same, it indicates a parallelogram.
B. Show that LN = MP.
This alone does not necessarily prove that LMNP is a parallelogram. Equal lengths of opposite sides are a property of parallelograms, but it is not sufficient on its own.
C. Show that LM = NP and MN = LP.
This alone does not necessarily prove that LMNP is a parallelogram. Equal lengths of pairs of opposite sides are a property of parallelograms, but it is not sufficient on its own.
D. Show that the slope of LN multiplied by the slope of MP is equal to -1.
This is a property of parallelograms. If the product of the slopes of one pair of opposite sides is -1, it indicates a parallelogram.
Therefore, options A and D are the ones that would help show that quadrilateral LMNP is a parallelogram.