Answer: MP = 2
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Work Shown:
LK = 1 is given
LK = KN since the diagonals of a parallelogram bisect one another. The same can be said about PK = KM.
Since all squares are a rectangle, this means LN = MP. Any rectangle has its diagonals be congruent.
So,
LN = LK+KN
LN = 1+1
LN = 2
MP = LN
MP = 2