MJH = 120
Let TJH = x
You’re told MJT is 4 times TJH
So you have 4x + x = 120
Simplify: 5x = 120
Divide both sides by 5:
X = 24
TJH = x = 24 degrees.
JT is a bisector so both TJH and TJA are the same. So TJA is also 24 degrees
So MJA = 120 - 24 - 24 = 72
MJA = 72 degrees