Circles M and K are congruent, QR is congruent to LN and OP is congruent to VW. Find y.

we have give the two circles and chords QR is congruent to LN.
it means QR=LN
-x=y+8
and OP is congruent to VW
OP=VW
x=3y+8
we know that -x=y+8
+x=-y-8
we need to equate two equations
we know that chords subtends in two congruent circles are same .
-y-8=3y+8
4y=16
y=4.