All the interior angles of a triangle must add up to 180 degrees.
This means that the sum of x, 102, and 31 must equal 180.
[tex]x+31+102=180[/tex]
[tex]x+133=180[/tex]
Subtract both sides by 133
[tex]x=180-133[/tex]
[tex]=47[/tex]
The measure of x is 47 degrees. You can verify this by adding all the interior angles. I hope this helps! :)
~AgentCozmo4, Moderator
