Question

what is the sum of the measures of the exterior angles of a decagon. if necessary round to the nearest tenth

Answer 1

I will assume that is a regular dodecagon

Number of sides=12

step 1

Find out the sum of the interior angles

S=180(n-2)

n=12

S=180(12-2)

S=180(10)=1,800 degrees

The measure of each interior angle is

1,800/12=150 degrees

step 2

Remember that

The sum of each interior angle and its exterior angle is always equal to 180 degrees

so

interior angle=150 degrees

therefore

the measure of each exterior angle is 30 degrees