Question

For what value of y must QRST be a parallelogram?
A: 1
B: 2
C: 3
D: 0.5

Answer 1

A

Explanation:

Diagonals of a parallelogram bisect each other.

3x = 3

x = 1

y = x

y = 1

Answer 2

In a parallelogram, the parts in which each diagonal cuts the other are congruent.

This means that we must have

`\begin{cases}3=3x\\x=y\end{cases}`

From the first equation we can deduce x=1, and thus y=x=1.