Answer:
∠ FNT = 120°
Explanation:
14a - 20 and 7a + 50 are corresponding angles and congruent, thus
14a - 20 = 7a + 50 ( subtract 7a from both sides )
7a - 20 = 50 ( add 20 to both sides )
7a = 70 ( divide both sides by 7 )
a = 10
Thus
∠ MNG = 7a + 50 = 7(10) + 50 = 70 + 50 = 120°, hence
∠ FNT = 120° ( vertical to ∠ MNG )