Itrs is known that the sum of the internal angles of a triangle is 180°.
So, if a triangle has angles A, B and C, we have:
[tex]A+B+C=180\degree[/tex]
a)
In this case, we know that values of the angles 68° and 53°. Let the missing one be x, so:
[tex]\begin{gathered} 68\degree+53\degree+x=180\degree \\ 121\degree+x=180\degree \\ x=180\degree-121\degree \\ x=59\degree \end{gathered}[/tex]
So, the missing angles is 59°.
