Answer:
D
Step-by-step explanation
I'd say it's PQR and TSR cause they match up in terms of the order of vertexes, and then you've got the angles of P and T that are in the middle of PR and TR, which are equal, and the sides PQ and TS. The angles are in between the sides.
Since you have an equation equal to both x and y, you can either substitute the equation equal to x for x or the equation equal to y for y.
x=y-1
y=4-2x
I would substitute the y in using 4-2x
x=(4-2x)-1
x=3-2x
3x=3
x=1
Then plug in x and solve for y
1=y-1
2=y