Answer:
A
Step-by-step explanation:
Given that the triangles are congruent then corresponding angles are congruent, thus
∠ S = ∠ Y = 108°
∠ T = ∠ Z = 9n - 4
Given ∠ R = 6n + 1
The sum of the 3 angles in Δ RST = 180°
Sum the 3 angles and equate to 180, that is
6n + 1 + 108 + 9n - 4 = 180 , simplify
15n + 105 = 180 ( subtract 105 from both sides )
15n = 75 ( divide both sides by 15 )
n = 5 → A
