Y + 4 + 3(y+2)
y + 4 + 3y + 3*2
4y + 4 + 6
4y + 10
z^2 + z+ 4z^3 + 4z^2
5z^2 + z + 4z^3
1/4 (16 + 4p)
16/4 + 4p/4
4 + p
All triangles inner angles addition equals to 180°
So if you’re finding the x° then minus the other angles from 180°
23°+129°+x=180°
x=180°-129°-23°
x=28°
I hope this helped :)
Addition because 8-2 = 6 and then you add the 4
