Answer:
<RST = 49°
Step-by-step explanation:
From the figure we can see that, a triangle RST.
<R = 79° and also given an exterior angle at T,exterior angle of T = 128°
To find <RTS
<RTS and exterior angle at T are linear pair.
Sum of linear pair angles is 180°
Therefore, <RTS + 128° = 180°
<RTS = 180 -128 = 52°
To find <RST
In triangle RST, <R + <S + <T = 180
(Angle sum property of a triangle)
<R = 79°, <T = 52° <S =<RST = ?
<RST = 180 - (<R + <T) = 180 - (79 + 52 ) = 180 - 131 = 49°
Therefore <RST = 49°
