Question

Determine the measure of the interior angle at vertex D. A. 27 B. 162 C. 20 D. 36

Answer 1

The sum of interior angles of a polygon with n sides is
`(n-2)\cdot180`

In this case
`n=6`

Therefore

`4\cdot9x+2\cdot2x=(6-2)\cdot180\\36x+4x=4\cdot180\\40x=720\\x=18`

`9x=9\cdot18=162`

So B

Answer 2

162°

Explanation:

The shape is a hexagon, so the interior angles equal 720. (N-2)*180=720

9x+9x+9x+2x+9x+2x=720

40x=720

x=720/40

x=18

D=9x=9(18)=162°