Question

Name the polygon whose interior angles add up to ${720}^{\circ }$.

• A. Decagon
• B. Heptagon
• C. Pentagon
• D. Hexagon

Answer 1

The correct option is D Hexagon

Give: Sum of interior angles $={720}^{\circ }$

The formula for calculating the sum of interior angles of a polygon is $(n-2)\times {180}^{\circ }$.

Therefore, $(n-2)\times {180}^{\circ }={720}^{\circ }$

$(n-2)=\frac{{720}^{\circ }}{{180}^{\circ }}=4$

$(n-2)=4$

$n=6$

The polygon has $6$ sides which means it is a hexagon.