Answer
The measure of the third angle is calculated by angle sum property.
Work Step by Step
According to angle sum property, the sum of all the angles of a triangle is equal to\[180{}^\circ \] and the measure of the third angle is calculated by angle sum property.
Example:
In a triangle ABC, \[\angle 2=46{}^\circ \]and\[\angle 3=67{}^\circ \]. It is required to compute the value of angle\[\angle 1\].
According to angle sum property, the sum of all the angles of a triangle is\[180{}^\circ \]. The calculation is shown below as:
\[\begin{align}
& \angle 1+\angle 2+\angle 3=180{}^\circ \\
& \angle 1+46{}^\circ +67{}^\circ =180{}^\circ \\
& \angle 1=180{}^\circ -113{}^\circ \\
& \angle 1=67{}^\circ
\end{align}\]
The triangle can be shown as mentioned below:
