For what value of y must QRST be a parallelogram?
A: 1
B: 2
C: 3
D: 0.5
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Answer:
A
Step-by-step explanation:
Diagonals of a parallelogram bisect each other.
3x = 3
x = 1
y = x
y = 1
In a parallelogram, the parts in which each diagonal cuts the other are congruent.
This means that we must have
[tex]\begin{cases}3=3x\\x=y\end{cases}[/tex]
From the first equation we can deduce x=1, and thus y=x=1.