Answer:
Below in bold,
Explanation:
The angles in a triangle add up to 180 degrees.
So the equation is:
7x + 8 + 4x + x + 4 = 180
12x + 12 = 180 <-------- Required equation
12x = 168
x = 14.
m< L = 14 + 4 = 18 degrees
m< M = 7(14) + 8 = 106 degrees
m< N = 4(14)= 56 degrees