Answer:
Step-by-step explanation:
X+x+1+x+2=4x-9
3x+3=4x-9
X=12
sum of the interior angles x and y gives the exterior angle z
(4n-18)°+(n+8)°=(133-6n)°
4n°-18°+n°+8°=133°-6n°
4n°+n°-18°+8°=133°-6n°
5n°-10°=133°-6n°
5n°+6n°=133°+10°
11n°=143°
11°n/11°=143°/11°
n=13
exterior angle=133-6×13
=133-78
=55
