Question

Two angles of a triangle are ${65}^{\circ }$ and ${45}^{\circ }$ then the third angle is:

• A. ${60}^{\circ }$
• B. ${80}^{\circ }$
• C. ${70}^{\circ }$
• D. ${75}^{\circ }$

Answer 1

The correct option is C

${70}^{\circ }$

Let the third angle be 'x'
From angle sum property of a triangle, we have
${65}^{\circ }+{45}^{\circ }+x^{\circ }={180}^{\circ }\Rightarrow x={180}^{\circ }-{110}^{\circ }\Rightarrow x={70}^{\circ }$