question_answer

If two angles of a triangle measure \[45{}^\circ \] and \[60{}^\circ ,\]then which of the following angle cannot be the measure of one of the exterior angles of the triangle?

A)  \[105{}^\circ \]                        

B)  \[120{}^\circ \]          

C)  \[140{}^\circ \]             

D)  \[135{}^\circ \]

Correct Answer: C

Solution :

(c): We can easily see that three exterior \[\angle \,les\] are \[105{}^\circ ,\text{ }135{}^\circ ,\text{ }120{}^\circ \] therefore (c) \[140{}^\circ \]is the answer.