Answer:
C) 12
Step-by-step explanation:
Since triangles MNO and PQR are congruent to each other, then their respective line segments are congruent to each other as well.
So since MO is congruent to PR, we can solve for y:
2y+3=21
2y=18
y=9
Also, since MN is congruent to PQ, we can solve for x:
10=4x-2
12=4x
3=x
x=3
QR is the sum of x and y, so the sum would be 3+9=12, therefore, the length of QR is C) 12
