Answer:
139°
Explanation:
Let the measure of the third angle = x
The sum of the measures of angles in a triangle is 180 degrees.
Thus:
[tex]31\degree+10\degree+x=180\degree[/tex]We solve the equation for x:
[tex]\begin{gathered} 41\degree+x=180\degree \\ x=180\degree-41\degree \\ x=139\degree \end{gathered}[/tex]The measure of the third angle is 139°.
