Question 501872
It sounds as if angles LKM and MRN = LKN, which is 145 degrees.
2x + 10 + 4x - 3 = 145
6x + 7 = 145
6x = 138
x = 23
LKM = 2(23) + 10 = 56 degrees
MKN = 4(23) - 3 =  89 degrees
56 degrees + 89 degrees = 145 degrees.
This does check.
Cleomenius.