Answer:
JK = 6
Explanation:
Because of parallel lines, we can say:
ΔJKL is similar to ΔJHI
Corresponding sides are proportional. We can say:
JK is to KL as JH is to HI
From the given info, we can further say:
JK is to 21, as, 14 is to 49
We can write equation and solve for JK:

JK = 6