I would help you but the picture is blurry
We Need to First Do 12 - 5.
12 - 5 = 7.
[7 * 12] <span>÷ 6
12 * 7 = 84.
84 </span><span>÷ 6
This Is Our Answer:
14.</span>
So you question is most likely about a triangle DEF with the 3 angles being named D, E, F. The triangle would look something like the image attached below.
If that is what is being asked then i need more info to answer but
By Definition it would be 180 degrees.
just divide 17 by 6 and you'll get your mixed number:
2 5/6
Idk sorry I am not that good at math :)