Question

If one interior angle of an octagon is ${142}^{\circ }$ and each of the other angles are $x^{\circ }$, then x = ___

• A. ${180}^{\circ }$
• B. ${143}^{\circ }$
• C. ${140}^{\circ }$
• D. ${134}^{\circ }$

Answer 1

The correct option is D

${134}^{\circ }$

Sum of interior angles of an octagon = $(8-2)\times {180}^{\circ }$

142 + 7x = $6\left({180}^{\circ }\right)$

7x = 1080 - 142

$7x={938}^{\circ }$

$x={134}^{\circ }$

Hence (D)