Question

The measures of the angles of △RST are given by the expressions in the table. Angle Measure
R 31°
S ​(x+4)∘
T ​(3x+9)∘
Find the value of x. Then find the m∠S and m∠T.



Enter your answers in the boxes.
x =

​ m∠S= ​
º

​ m∠T= ​
º

Answer 1

Because a triangles angles add up to 180 degrees, we can say that 

x+4+3x+9+31=180 degrees.

The question is now a simple algebraic expression.

4x+44=180
Subtract 44 on both sides

4x=136
Divide by 4 on both sides

x= 34

m∠S= x+4, (34)+4, 38
m∠S=38 degrees

m∠T= 3x+9, 3(34)+9, 102+9, 111
m∠T=111 degrees

I hope this helps and please mark brainiest answer :D