a polygon with three side is called triangle.
we know sum of all angle of triangle is [tex]180^{\circ}[/tex]
here we are given three angles are
[tex]45^{\circ}62^{\circ}k^{\circ}[/tex]
this implis
[tex]45^{\circ}\dotplus 62^{\circ}\dotplus k^{\circ}=180^{\circ} now107^{\circ}+k^{\circ}=180^{\circ}this impliesk^{\circ}=180^{\circ}-107^{\circ}=73^{\circ}[/tex]
hence the required angle [tex]k^{\circ}=73^{\circ}[/tex]
