Identify the sum of the interior angle measures of a convex dodecagon. !

choice D. 1800

Work Shown:

A dodecagon has 12 sides (do = 2, deca = 10, dodeca = do+deca = 2+10 = 12). An alternative name to "dodecagon" is "twelve-gon" in which we can write "12-gon" for short.

The value n is the number of sides, so n = 12 is plugged into the formula below

S = 180(n-2)

S = 180(12-2)

S = 180(10)

S = 1800

If this were a regular dodecagon (all sides congruent), then E = 360/n = 360/12 = 30 is the measure of each exterior angle. So 180-E = 180-30 = 150 is the measure of each interior angle. So n*(180-E) = n*150 = 12*150 = 1800 is another way to get the answer. Again this is only assuming that the figure is regular. Otherwise, you should use the formula mentioned earlier.

the answer is (4,3)

since the rule for r0, 90º is (-y,x) and it was already applied to form the image, all you have to do is reverse the answer using this formula.

the answer is c. 23/3