In ΔQRS,
Q
S
‾
QS
​
is extended through point S to point T,
m
∠
Q
R
S
=
(
x
+
8
)
∘
m∠QRS=(x+8)
∘
,
m
∠
R
S
T
=
(
4
x
+
11
)
∘
m∠RST=(4x+11)
∘
, and
m
∠
S
Q
R
=
(
x
+
13
)
∘
m∠SQR=(x+13)
∘
. Find
m
∠
R
S
T
.
m∠RST.