Answer:
x = 21
Explanation:
You need to understand the concept of linear angles and supplementary angles.
The square in the K*J angle is a 90 degree symbol, and if you add the 15 degrees making up that K*N angle, it makes 105 degs.
Since the lines KL and MN are intersecting, they are adjacent, so the angle K*M and N*L are equivalent, and K*N and M*L are equivalent.
This means that M*L is also 105 degs.
If 105 degs is equal to 5x, you can simply divide to find the unit rate of x.
105/5