Question

Find the unknown marked angles in the given figure:

Answer 1

Step: Find value of b

By the angle sum property of the triangle,

${50}^{\circ }$ + $b^{\circ }$ + $b^{\circ }$ = ${180}^{\circ }$

⇒ $2b^{\circ }$ = ${180}^{\circ }$ - ${50}^{\circ }$

⇒ $2b^{\circ }$ = ${130}^{\circ }$

⇒ $b^{\circ }$ = ${65}^{\circ }$

Hence, the unknown angle $b^{\circ }$ is ${65}^{\circ }$.