Answer:
LM = 23
Step-by-step explanation:
Opposite sides of a parallelogram are the same length, so you can use sides LO and MN to find the value of x:
21 = 4x -7
28 = 4x
7 = x
Then use that value in the expression for the side length NO:
NO = 3x +2 = 3·7 +2 = 23
Since LM is the same length as NO, LM = 23.
