I'm able to solve this thanks to my Canadian education.

>>77073291
A1, A3, A3 = 3 inner angles of topmost triangle

E+C=180-A2
D+B=180-A3
=>E+C+D+B = 360-(A2+A3)
=>A+E+C+D+B = 360-(A1+A2+A3)
=>sum = 360-180 = 180
answer is 180
is this supposed to be hard?

>>77073674
they overwork you kids in those Asian schools.

>>77073291
umm idk lol

I didn't know Canadian education were as shitty as American

not a clue

>>77073291
...
no wonder chinks hae an easy time in canada.
thats why you shouldn't spend your JHS masturbating to art class teacher, moron

>>77073291
>HiroHACKo HACKraki can't even draw a star right

Jojofags will defend this

It's a star. Think about the pentagon in the center.

>>77074701
>>77074616
>>77074644

>>77074881
Do you expect a birthmark to be 100% straight?

>>77073674
uh, are those A1, A2, A3 counter-clockwise?
your explanation is highly prone to misleading.
i think its more intuitive this way (clockwise).
180-(E+C)= 180-(A2) => A2=E+C
180-(B+D)= 180-(A3) => A3=D+B
A1+A2+A3=A1+E+C+D+B=180

>>77073674
>>77075683

Jesus Christ.

File: awsdwdwd.png (20KB, 334x334px) Image search: [Google]

20KB, 334x334px

>>77075683
i couldnt be fucked to write down all the little steps so get it however you want, but your equation A2=E+C is wrong though

it's something like this
E+C+Z1=180
AZE+Z1=180
=>AZE=E+C

that's how i got E+C=180-A2

>>77075683
>>77078381
actually you're not wrong, i mistook A2 and A3, happens when we arent looking at the same figurine

>>77078381
>>77078521
yeah i just figure that your explanation albeit correct, bit confusing at times especially if people hadn't figure out how you did that final substitution. turns out our method is exactly the same

lol at idiots doing algebra..

its a fucking star and says INTERNAL right there... it has to be 360/2

>>77079159
its for your fellow countrymen who obviously skipped his 7th grade math class that solving this shit is basically an achievement for him, using theorem to explain math problem is bullshit, thats why we bother with how the explanation being presented instead of the answer itself

>>77073291
Solution with less algebra:

Each corner of the pentagram is joined by 3 other angles to make up 360 degrees, with 2 being angles from the triangle that is not A,B,C,D or E and the other being exactly the same in size as the corresponding pentagon angle. To get the sum of angles from triangles that is not A,B,C,D or E, just do 360*5 - 180*3*2(double of the pentagram's total angles) to get 180 * 4. subtract this from 180 * 5(as there is 5 triangles) to get A + B + C + D + E, which is 180.