Answers: x = 3 and y = 13
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Explanation:
For any parallelogram, the diagonals always cut each other in half.
This means the pieces that are y+5 and 18 cm long are equal
y+5 = 18
y = 18-5
y = 13
And so are the pieces that are x+y and 16 cm long
x+y = 16
x+13 = 16
x = 16-13
x = 3
Side note: the term "bisecting" is often used when saying "cutting in half".
