Answer:
XY = 7
Explanation:
We are given the isosceles trapezoid WXYZ
[tex]\begin{gathered} WX=12 \\ XY=y+1 \\ YZ=y+6 \\ WZ=? \end{gathered}[/tex]
One of the properties of an isosceles trapezoid is that "the non-parallel sides (legs) are congruent"
Mathematically,
[tex]\begin{gathered} WX\cong YZ \\ \Rightarrow12=y+6 \\ 12=y+6 \\ \text{Subtract ''6'' from both sides, we have:} \\ 12-6=y \\ 6=y \\ y=6 \end{gathered}[/tex]
We will proceed to obtain length XY as shown below:
[tex]\begin{gathered} XY=y+1 \\ but:y=6 \\ XY=6+1 \\ XY=7 \\ \\ \therefore XY=7 \end{gathered}[/tex]
Therefore, the length of XY equals 7. The answer is the first option
