Answer:
8 2/3 units.
Explanation:
As bothe the circles and the arcs are congruent, the chords QR and LN are also congruent.
So LN = QR
x + 7 = 4x + 2
7 - 2 = 4x - x
3x = 5
x = 5/3.
Therefore the length of QR = 4x + 2
= 4(5/3) + 2
= 20/3 + 6/3
= 26/3
= 8 2/3 units.