Answer:
17. (c) 6 cm
18. (c) 6 cm
Step-by-step explanation:
You want the measures of LM and KN in parallelogram KLMN with LM marked 3x cm and KN marked x+4 cm.
Opposite sides
The opposite sides of a parallelogram are the same length, so we have ...
LM = KN
3x = x +4
2x = 4
x = 2
3x = 3(2) = 6 . . . . cm
17. Side LM is 6 cm, choice C.
18. Side KN is 6 cm, choice C.
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Additional comment
The other two sides are also equal to each other. This tells you y=3 cm, so KL = MN = 6 cm as well. This parallelogram is a rhombus.
This means the angles marked 25° and 35° are in error. Those angles must be identical if the side lengths are congruent. (The expression for side MN should be closer to y+2.21 for the given angles.)
